WorldWideScience

Sample records for membrane lipid peroxidation

  1. Ultraviolet- and sunlight-induced lipid peroxidation in liposomal membrane

    International Nuclear Information System (INIS)

    Mandal, T.K.; Chatterjee, S.N.

    1980-01-01

    Ultraviolet radiation and sunlight caused lipid peroxidation in the liposomal membrane (as detected by measurement of the oxidation index, A 233 /A 215 , and the amount of malondialdehyde formed) and made the membrane leaky (as revealed by the release of the trapped chromate anions). The oxidation index and the formation of malondialdehyde increased linearly with increasing dose of radiation and depended significantly on the dose rate. The effects were smaller in liposomes derived from Vibrio cholerae phospholipid than in those derived from egg lecithin. The effects of the radiation dose and dose rate on hemolysis and peroxidation (MDA formation) of the erythrocyte membrane followed a similar pattern. A direct correlation between the percentage leakage of chromate (Y) and the oxidation index (X) of the liposomal system was obtained as Y = 236.5 x X

  2. Radiation-induced lipid peroxidation: influence of oxygen concentration and membrane lipid composition

    International Nuclear Information System (INIS)

    Wolters, H.; Tilburg, C.A.M. van; Konings, A.W.T.

    1987-01-01

    Radiation -induced lipid peroxidation phospholipid liposomes was investigated in terms of its dependence on lipid composition and oxygen concentration. Non-peroxidizable lipid incorporated in the liposomes reduced the rate of peroxidation of the peroxidizable phospholipid acyl chains, possibly by restricting the length of chain reactions. The latter effect is believed to be caused by interference of the non-peroxidizable lipids in the bilayer. At low oxygen concentration lipid peroxidation was reduced. The cause of this limited peroxidation may be a reduced number of radical initiation reactions possibly involving oxygen-derived superoxide radicals. Killing of proliferating mammalian cells, irradiated at oxygen concentrations ranging from 0 to 100%, appeared to be independent of the concentration of peroxidizable phospholipids in the cell membranes. This indicates that lipid peroxidation is not the determining process in radiation-induced reproductive cell death. (author)

  3. Membrane lipid peroxidation by UV-A: Mechanism and implications

    International Nuclear Information System (INIS)

    Bose, B.; Agarwal, S.; Chatterjee, S.N.

    1990-01-01

    UV-A produced a dose-dependent linear increase of lipid peroxidation in liposomal membrane, as detected by the assay of (i) conjugated dienes, (ii) lipid hydroperoxides, (iii) malondialdehydes (MDA), and (iv) the fluorescent adducts formed by the reaction of MDA with glycine and also a linear dose-dependent increase of [ 14 C]glucose efflux from the liposomes. UV-A-induced MDA production could not be inhibited by any significant degree by sodium formate, dimethyl sulfoxide, EDTA, or superoxide dismutase but was very significantly inhibited by butylated hydroxytoluene, alpha-tocopherol, sodium azide, L-histidine, dimethylfuran, and beta-carotene. MDA formation increased with an increase in the D 2 O content in water, leading to a maximal amount of nearly 50% enhancement of lipid peroxidation in 100% D 2 O vis-a-vis water used as dispersion medium. The experimental findings indicate the involvement of singlet oxygen as the initiator of the UV-A-induced lipid peroxidation

  4. INTERACTION OF ALDEHYDES DERIVED FROM LIPID PEROXIDATION AND MEMBRANE PROTEINS.

    Directory of Open Access Journals (Sweden)

    Stefania ePizzimenti

    2013-09-01

    Full Text Available A great variety of compounds are formed during lipid peroxidation of polyunsaturated fatty acids of membrane phospholipids. Among them, bioactive aldehydes, such as 4-hydroxyalkenals, malondialdehyde (MDA and acrolein, have received particular attention since they have been considered as toxic messengers that can propagate and amplify oxidative injury. In the 4-hydroxyalkenal class, 4-hydroxy-2-nonenal (HNE is the most intensively studied aldehyde, in relation not only to its toxic function, but also to its physiological role. Indeed, HNE can be found at low concentrations in human tissues and plasma and participates in the control of biological processes, such as signal transduction, cell proliferation and differentiation. Moreover, at low doses, HNE exerts an anti-cancer effect, by inhibiting cell proliferation, angiogenesis, cell adhesion and by inducing differentiation and/or apoptosis in various tumor cell lines. It is very likely that a substantial fraction of the effects observed in cellular responses, induced by HNE and related aldehydes, be mediated by their interaction with proteins, resulting in the formation of covalent adducts or in the modulation of their expression and/or activity. In this review we focus on membrane proteins affected by lipid peroxidation-derived aldehydes, under physiological and pathological conditions.

  5. Ultraviolet radiation-induced lipid peroxidation in liposomal membrane: modification by capsaicin

    Energy Technology Data Exchange (ETDEWEB)

    De, A. K.; Ghosh, J. J.; Mandal, T. K. [University College of Science, Department of Biochemistry, 35 Ballygunge Circular Road, Calcutta 700-019 (India)

    1993-07-01

    Ultraviolet-radiation has been reported to cause lipid peroxidation in the liposomal membrane. In the present study, treatment with capsaicin, (8-methyl-n-vanillyl-6-nonenamide), the pungent principle of red hot pepper, was shown to modify UV-induced lipid peroxidation in the liposomal membrane. Treatment with low doses of capsaicin (less than 0.1 μg/mL of phosphatidyl choline liposome) produced a significant increase in UV-induced lipid peroxidation, while high doses (0.1-0.5 μg/mL of PC liposome) caused a significant decrease of UV-induced peroxidation.

  6. Ultraviolet radiation-induced lipid peroxidation in liposomal membrane: modification by capsaicin

    International Nuclear Information System (INIS)

    De, A.K.; Ghosh, J.J.; Mandal, T.K.

    1993-01-01

    Ultraviolet-radiation has been reported to cause lipid peroxidation in the liposomal membrane. In the present study, treatment with capsaicin, (8-methyl-n-vanillyl-6-nonenamide), the pungent principle of red hot pepper, was shown to modify UV-induced lipid peroxidation in the liposomal membrane. Treatment with low doses of capsaicin (less than 0.1 μg/mL of phosphatidyl choline liposome) produced a significant increase in UV-induced lipid peroxidation, while high doses (0.1-0.5 μg/mL of PC liposome) caused a significant decrease of UV-induced peroxidation

  7. Lipid peroxidation in liver homogenates. Effects of membrane lipid composition and irradiation

    International Nuclear Information System (INIS)

    Vaca, C.; Ringdahl, M.H.

    1984-01-01

    The rate of lipid peroxidation has been followed in whole liver homogenates from mice using the TBA-method. Liver homogenates with different membrane fatty acid composition were obtained from mice fed diets containing different sources of fat i.e. sunflower seed oil (S), coconut oil (C) and hydrogenated lard (L). The yields of the TBA-chromophore (TBA-c) were 4 times higher in the liver homogenates S compared to C and L after 4 hour incubation at 37 0 C. Irradiation of the liver homogenates before incubation inhibited the formation of lipid peroxidation products in a dose dependent way. The catalytic capacity of the homogenates was investigated, followed as the autooxidation of cysteamine or modified by addition of the metal chelator EDTA. The rate of autooxidation of cysteamine, which is dependent on the presence of metal ions (Fe/sup 2+/ or Cu/sup 2+/), was decreased with increasing dose, thus indicating an alteration in the availability of metal catalysts in the system. The addition of Fe/sup 2+/ to the system restored the lipid peroxidation yields in the irradiated systems and the presence of EDTA inhibited the formation of lipid peroxidation products in all three dietary groups. It is suggested that irradiation alters the catalytic activity needed in the autooxidation processes of polyunsaturated fatty acids

  8. Radiation effects on membranes. I. Vitamin E deficiency and lipid peroxidation

    International Nuclear Information System (INIS)

    Konings, A.W.T.; Drijver, E.B.

    1979-01-01

    Mice which had received a vitamin E-deficient diet from weaning on, were more sensitive to x irradiation than were normal mice, LD/sub 50/30/ being decreased by 0.25 Gy. The vitamin E-deficient mice also showed an increased spleen shrinkage. The cellular membranes of the vitamin E-deficient mice were more vulnerable to lipid peroxidation. X irradiation in vivo shortened the lag period prior to rapid lipid peroxidation as measured in vitro. Injection of the mice with glutathione prior to x irradiation protected the membranes in the in vitro test of peroxidation capacity as was demonstrated by an extended lag period. The possible meaning of these results with respect to the concept that membranes may be important sites for radiation damage is discussed

  9. Electron paramagnetic resonance study of lipid and protein membrane components of erythrocytes oxidized with hydrogen peroxide

    Energy Technology Data Exchange (ETDEWEB)

    Mendanha, S.A.; Anjos, J.L.V.; Silva, A.H.M.; Alonso, A. [Instituto de Física, Universidade Federal de Goiás, Goiânia, GO (Brazil)

    2012-04-05

    Electron paramagnetic resonance (EPR) spectroscopy of spin labels was used to monitor membrane dynamic changes in erythrocytes subjected to oxidative stress with hydrogen peroxide (H{sub 2}O{sub 2}). The lipid spin label, 5-doxyl stearic acid, responded to dramatic reductions in membrane fluidity, which was correlated with increases in the protein content of the membrane. Membrane rigidity, associated with the binding of hemoglobin (Hb) to the erythrocyte membrane, was also indicated by a spin-labeled maleimide, 5-MSL, covalently bound to the sulfhydryl groups of membrane proteins. At 2% hematocrit, these alterations in membrane occurred at very low concentrations of H{sub 2}O{sub 2} (50 µM) after only 5 min of incubation at 37°C in azide phosphate buffer, pH 7.4. Lipid peroxidation, suggested by oxidative hemolysis and malondialdehyde formation, started at 300 µM H{sub 2}O{sub 2} (for incubation of 3 h), which is a concentration about six times higher than those detected with the probes. Ascorbic acid and α-tocopherol protected the membrane against lipoperoxidation, but did not prevent the binding of proteins to the erythrocyte membrane. Moreover, the antioxidant (+)-catechin, which also failed to prevent the cross-linking of cytoskeletal proteins with Hb, was very effective in protecting erythrocyte ghosts from lipid peroxidation induced by the Fenton reaction. This study also showed that EPR spectroscopy can be useful to assess the molecular dynamics of red blood cell membranes in both the lipid and protein domains and examine oxidation processes in a system that is so vulnerable to oxidation.

  10. Urea application promotes amino acid metabolism and membrane lipid peroxidation in Azolla.

    Directory of Open Access Journals (Sweden)

    Jiana Chen

    Full Text Available A pot experiment was conducted to evaluate the effect of urea on nitrogen metabolism and membrane lipid peroxidation in Azolla pinnata. Compared to controls, the application of urea to A. pinnata resulted in a 44% decrease in nitrogenase activity, no significant change in glutamine synthetase activity, 660% higher glutamic-pyruvic transaminase, 39% increase in free amino acid levels, 22% increase in malondialdehyde levels, 21% increase in Na+/K+- levels, 16% increase in Ca2+/Mg2+-ATPase levels, and 11% decrease in superoxide dismutase activity. In terms of H2O2 detoxifying enzymes, peroxidase activity did not change and catalase activity increased by 64% in urea-treated A. pinnata. These findings suggest that urea application promotes amino acid metabolism and membrane lipid peroxidation in A. pinnata.

  11. Urea application promotes amino acid metabolism and membrane lipid peroxidation in Azolla.

    Science.gov (United States)

    Chen, Jiana; Huang, Min; Cao, Fangbo; Pardha-Saradhi, P; Zou, Yingbin

    2017-01-01

    A pot experiment was conducted to evaluate the effect of urea on nitrogen metabolism and membrane lipid peroxidation in Azolla pinnata. Compared to controls, the application of urea to A. pinnata resulted in a 44% decrease in nitrogenase activity, no significant change in glutamine synthetase activity, 660% higher glutamic-pyruvic transaminase, 39% increase in free amino acid levels, 22% increase in malondialdehyde levels, 21% increase in Na+/K+- levels, 16% increase in Ca2+/Mg2+-ATPase levels, and 11% decrease in superoxide dismutase activity. In terms of H2O2 detoxifying enzymes, peroxidase activity did not change and catalase activity increased by 64% in urea-treated A. pinnata. These findings suggest that urea application promotes amino acid metabolism and membrane lipid peroxidation in A. pinnata.

  12. [The effects of electromagnetic pulse on fluidity and lipid peroxidation of mitochondrial membrane].

    Science.gov (United States)

    Wang, Changzhen; Cong, Jianbo; Xian, Hong; Cao, Xiaozhe; Sun, Cunpu; Wu, Ke

    2002-08-01

    To study the effects of intense electromagnetic pulse(EMP) on the biological effects of mitochondrial membrane. Rat liver mitochondrial suspension was exposed to EMP at 60 kV/m level. The changes of membrane lipid fluidity and membrane protein mobility were detected by ESR and spin label technique. Malondialdehyde(MDA) was detected by spectrophotometer. The mobility of membrane protein decreased significantly(P < 0.05). Correlation time (tau c) of control group was (0.501 +/- 0.077) x 10(-9)s, and tau c of EMP group was (0.594 +/- 0.049) x 10(-9)s, indicating that the mobility of protein was restricted. The fluidity of mitochondrial membrane increased significantly(P < 0.05) at the same time. Order parameter(S) of mitochondrial membrane lipid in control group was 0.63 +/- 0.01, while S of EMP group was 0.61 +/- 0.01(P < 0.05). MDA decreased significantly. The mobility and lipid peroxidation of mitochondrial membrane may be disturbed after EMP exposure.

  13. Effect of tea catechins on the structure of lipid membrane and beta-ray induced lipid peroxidation

    International Nuclear Information System (INIS)

    Kubota, M.; Haga, H.; Takeuchi, Y.; Okuno, K.; Yoshioka, H.; Yoshioka, H.

    2007-01-01

    Inhibiting effect of four tea catechins, (-)-epicatechin (EC), (-)-epicatechin gallate (ECG), (-)-epigallocatechin (EGC), (-)-epigallocatechin gallate (EGCG), on the lipid peroxidation induced by β-ray in tritiated water was examined using a spin probe method. 16-Doxylstearic acid (16NS) was incorporated into the liposome prepared from egg yolk phosphatidylcholine and the rate of the decrease of ESR intensity of 16NS was used as a measure of the inhibiting effect. In the low concentration region below 10 -5 M, catechins showed their inhibitions on the lipid peroxidation according to the order of ECG>EGCG>EC>EGC. This result was explained by a model that the initiator of the peroxidation is the hydroxyl radical (·OH) and the catechins adsorbed on the lipid membrane surface acting as scavengers of ·OH. In the high concentration range, however, the effect was diverse and it decreased with the increase of it in the case of EGCG. EGCG in this range was considered to enter into the interior of the membrane and break the structure, which causes the decrease of 16NS. Observation with transmission electron microscope (TEM) revealed that the size of the liposome became larger with the increasing concentration of EGCG and finally it was broken into fragments, showing that EGCG broadened the area of the liposome as expected from the result of ESR. (author)

  14. Soluble products of Escherichia coli induce mitochondrial dysfunction-related sperm membrane lipid peroxidation which is prevented by lactobacilli.

    Directory of Open Access Journals (Sweden)

    Arcangelo Barbonetti

    Full Text Available Unidentified soluble factors secreted by E. coli, a frequently isolated microorganism in genitourinary infections, have been reported to inhibit mitochondrial membrane potential (ΔΨm, motility and vitality of human spermatozoa. Here we explore the mechanisms involved in the adverse impact of E. coli on sperm motility, focusing mainly on sperm mitochondrial function and possible membrane damage induced by mitochondrial-generated reactive oxygen species (ROS. Furthermore, as lactobacilli, which dominate the vaginal ecosystem of healthy women, have been shown to exert anti-oxidant protective effects on spermatozoa, we also evaluated whether soluble products from these microorganisms could protect spermatozoa against the effects of E. coli. We assessed motility (by computer-aided semen analysis, ΔΨm (with JC-1 dye by flow cytometry, mitochondrial ROS generation (with MitoSOX red dye by flow cytometry and membrane lipid-peroxidation (with the fluorophore BODIPY C11 by flow cytometry of sperm suspensions exposed to E. coli in the presence and in the absence of a combination of 3 selected strains of lactobacilli (L. brevis, L. salivarius, L. plantarum. A Transwell system was used to avoid direct contact between spermatozoa and microorganisms. Soluble products of E. coli induced ΔΨm loss, mitochondrial generation of ROS and membrane lipid-peroxidation, resulting in motility loss. Soluble factors of lactobacilli prevented membrane lipid-peroxidation of E. coli-exposed spermatozoa, thus preserving their motility. In conclusion, sperm motility loss by soluble products of E. coli reflects a mitochondrial dysfunction-related membrane lipid-peroxidation. Lactobacilli could protect spermatozoa in the presence of vaginal disorders, by preventing ROS-induced membrane damage.

  15. Promotion of radiation peroxidation in models of lipid membranes by caesium and rubidium counter-ions: micellar linolenic acids

    Energy Technology Data Exchange (ETDEWEB)

    Raleigh, J A; Kremers, W [Atomic Energy of Canada Ltd., Pinawa, Manitoba. Whiteshell Nuclear Research Establishment

    1978-11-01

    Caesium and rubidium counter-ions increase peroxidation in irradiated micelles of linoleic (18 : 2) and linolenic (18 :3) acids. The effect was specific to Cs/sup +/ and Rb/sup +/ in the alkali metal series. The effect was independent of the salts used (Cl/sup -/, NO/sub 3//sup -/, Cl0/sub 4//sup -/) and, therefore, independent of the chaotropic nature, and reactivity with hydroxyl radicals of Cl/sup -/, NO/sub 3//sup -/ and ClO/sub 4//sup -/. The promotion of peroxidation by Cs/sup +/ and Rb/sup +/ is interpreted in terms of their effect on fatty acid micelle structure. The dependence of radiation peroxidation on lipid structure in the micelles may be significant for studies of peroxidation in highly structured cell membranes.

  16. Near-ultraviolet radiation-induced lipid peroxidation and membrane effects in Escherichia coli and human skin fibroblasts

    International Nuclear Information System (INIS)

    Chamberlain, J.

    1987-01-01

    The first part of this thesis examines the response of an unsaturated fatty acid auxotroph, Escherichia coli K1060 to broad-band near-UV radiation. Sensitivity, lipid peroxidation and leakage of rubidium from irradiated cells were found to increase with increasing unsaturation of membrane fatty acids. The involvement of singlet oxygen was implicated by an increase in sensitivity, lipid peroxidation and leakage of rubidium following irradiation in deuterium oxide. Some factors influencing survival following irradiation were investigated, where lower growth rates were shown to enhance survival. In the second part, the study was extended to human fibroblasts where a normal human skin fibroblast strain, GM730 and a strain derived from an actinic reticuloid patient, AR6LO, are compared. Lipid peroxidation was measured in both cell lines following broad-band near-UV irradiation. Membrane activity, as assessed by the pinocytic uptake of 14 C-sucrose and its subsequent release from the cell, was measured. Near-UV irradiation was found to increase such activity in both strains. Vitamin E and Trolox-C were found to decrease this response in AR6LO but not GM730 cells. The final part consists of preliminary investigations into the near-UV induced peroxidation of fatty acids and liposomes, and the subsequent increase in the level of hydroperoxides in the hours following irradiation. (author)

  17. Responses of membrane lipid peroxidation and endogenous hormones of soybean seedlings to UV-B radiation and rare earth

    International Nuclear Information System (INIS)

    Yan Shengrong; Yang Chunhe; Zhang Yuequn

    2009-01-01

    [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/m2 and T2-0.45 W/m2), chlorophyll and indole-3-acetic acid(IAA) contents firstly decreased during the stress phase (1-5d) and then increased during the restoration phase (6-9d) while contents of malonadialdehyde(MDA) and abscisic acid(ABA) gradually increased during the imposition of UV-B radiation (1-5d) and subsequently decreased during recovery from UV-B stress (6-9d) . With adding of La (Ⅲ) with the concentration of 20mg•L-1, the decline/rise 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

  18. Linoleic Acid-Induced Ultra-Weak Photon Emission from Chlamydomonas reinhardtii as a Tool for Monitoring of Lipid Peroxidation in the Cell Membranes

    Science.gov (United States)

    Prasad, Ankush; Pospíšil, Pavel

    2011-01-01

    Reactive oxygen species formed as a response to various abiotic and biotic stresses cause an oxidative damage of cellular component such are lipids, proteins and nucleic acids. Lipid peroxidation is considered as one of the major processes responsible for the oxidative damage of the polyunsaturated fatty acid in the cell membranes. Various methods such as a loss of polyunsaturated fatty acids, amount of the primary and the secondary products are used to monitor the level of lipid peroxidation. To investigate the use of ultra-weak photon emission as a non-invasive tool for monitoring of lipid peroxidation, the involvement of lipid peroxidation in ultra-weak photon emission was studied in the unicellular green alga Chlamydomonas reinhardtii. Lipid peroxidation initiated by addition of exogenous linoleic acid to the cells was monitored by ultra-weak photon emission measured with the employment of highly sensitive charged couple device camera and photomultiplier tube. It was found that the addition of linoleic acid to the cells significantly increased the ultra-weak photon emission that correlates with the accumulation of lipid peroxidation product as measured using thiobarbituric acid assay. Scavenging of hydroxyl radical by mannitol, inhibition of intrinsic lipoxygenase by catechol and removal of molecular oxygen considerably suppressed ultra-weak photon emission measured after the addition of linoleic acid. The photon emission dominated at the red region of the spectrum with emission maximum at 680 nm. These observations reveal that the oxidation of linoleic acid by hydroxyl radical and intrinsic lipoxygenase results in the ultra-weak photon emission. Electronically excited species such as excited triplet carbonyls are the likely candidates for the primary excited species formed during the lipid peroxidation, whereas chlorophylls are the final emitters of photons. We propose here that the ultra-weak photon emission can be used as a non-invasive tool for the

  19. Linoleic acid-induced ultra-weak photon emission from Chlamydomonas reinhardtii as a tool for monitoring of lipid peroxidation in the cell membranes.

    Directory of Open Access Journals (Sweden)

    Ankush Prasad

    Full Text Available Reactive oxygen species formed as a response to various abiotic and biotic stresses cause an oxidative damage of cellular component such are lipids, proteins and nucleic acids. Lipid peroxidation is considered as one of the major processes responsible for the oxidative damage of the polyunsaturated fatty acid in the cell membranes. Various methods such as a loss of polyunsaturated fatty acids, amount of the primary and the secondary products are used to monitor the level of lipid peroxidation. To investigate the use of ultra-weak photon emission as a non-invasive tool for monitoring of lipid peroxidation, the involvement of lipid peroxidation in ultra-weak photon emission was studied in the unicellular green alga Chlamydomonas reinhardtii. Lipid peroxidation initiated by addition of exogenous linoleic acid to the cells was monitored by ultra-weak photon emission measured with the employment of highly sensitive charged couple device camera and photomultiplier tube. It was found that the addition of linoleic acid to the cells significantly increased the ultra-weak photon emission that correlates with the accumulation of lipid peroxidation product as measured using thiobarbituric acid assay. Scavenging of hydroxyl radical by mannitol, inhibition of intrinsic lipoxygenase by catechol and removal of molecular oxygen considerably suppressed ultra-weak photon emission measured after the addition of linoleic acid. The photon emission dominated at the red region of the spectrum with emission maximum at 680 nm. These observations reveal that the oxidation of linoleic acid by hydroxyl radical and intrinsic lipoxygenase results in the ultra-weak photon emission. Electronically excited species such as excited triplet carbonyls are the likely candidates for the primary excited species formed during the lipid peroxidation, whereas chlorophylls are the final emitters of photons. We propose here that the ultra-weak photon emission can be used as a non

  20. Effects of ionizing radiation on the peroxide content of a pure polyunsaturated lipid dispersion and of lipids and membranes derived from Acholeplasma laidlawii

    Energy Technology Data Exchange (ETDEWEB)

    Edwards, J.C.; Cramp, W.A. (Hammersmith Hospital, London (UK). M.R.C. Cyclotron Unit); Chapman, D. (Royal Free Hospital, London (UK))

    1984-01-01

    Dispersions of a pure unsaturated phospholipid, dilinoleoylphosphatidyl choline, formed conjugated diene hydroperoxides when irradiated in air with 7 MeV electrons (150 Gy and 300 Gy). Peroxide formation was optimized when the dispersions were irradiated in air at 37/sup 0/C at a dose rate of 5 Gy/min. No significant loss of linoleic acid from the irradiated phospholipid dispersions was observed after doses of 150 or 300 Gy. Small amounts of thiobarbituric acid-reactive material were formed in irradiated unsaturated phospholipid dispersions. However, lipids or membranes isolated from 48 hour cultures of Acholeplasma laidlawii grown in media supplemented with either linoleic or linolenic acid did not appear to be peroxidized by irradiation under the same conditions.

  1. Radiation induced peroxidation in model lipid systems

    International Nuclear Information System (INIS)

    Dahlan, K.Z.B.H.M.

    1981-08-01

    In the studies of radiation induced lipid peroxidation, lecithin-liposomes and aqueous micellar solutions of sodium linoleate (or linoleic acid) have been used as models of lipid membrane systems. The liposomes and aqueous linoleate micelles were irradiated in the presence of O 2 and N 2 O/O 2 (80/20 v/v). The peroxidation was initiated using gamma radiation from 60 Co radiation source and was monitored by measuring the increase in absorbance of conjugated diene at 232 nm and by the thiobarbituric acid (TBA) test. The oxidation products were also identified by GLC and GLC-MS analysis. (author)

  2. Microsomal lipid peroxidation as a mechanism of cellular damage. [Dissertation

    Energy Technology Data Exchange (ETDEWEB)

    Kornbrust, D.J.

    1979-01-01

    The NADPH/iron-dependent peroxidation of lipids in rat liver microsomes was found to be dependent on the presence of free ferrous ion and maintains iron in the reduced Fe/sup 2 +/ state. Chelation of iron by EDTA inhibited peroxidation. Addition of iron, after preincubation of microsomes in the absence of iron, did not enhance the rate of peroxidation suggesting that iron acts by initiating peroxidative decomposition of membrane lipids rather than by catalyzing the breakdown of pre-formed hydroperoxides. Liposomes also underwent peroxidation in the presence of ferrous iron at a rate comparable to intact microsomes and was stimulated by ascorbate. Carbon tetrachloride initiated lipid peroxidation in the absence of free metal ions. Rates of in vitro lipid peroxidation of microsomes and homogenates were found to vary widely between different tissues and species. The effects of paraquat on lipid peroxidation was also studied. (DC)

  3. Acid phosphatase and lipid peroxidation in human cataractous lens epithelium

    Directory of Open Access Journals (Sweden)

    Vasavada Abhay

    1993-01-01

    Full Text Available The anterior lens epithelial cells undergo a variety of degenerative and proliferative changes during cataract formation. Acid phosphatase is primarily responsible for tissue regeneration and tissue repair. The lipid hydroperoxides that are obtained by lipid peroxidation of polysaturated or unsaturated fatty acids bring about deterioration of biological membranes at cellular and tissue levels. Acid phosphatase and lipid peroxidation activities were studied on the lens epithelial cells of nuclear cataract, posterior subcapsular cataract, mature cataract, and mixed cataract. Of these, mature cataractous lens epithelium showed maximum activity for acid phosphatase (516.83 moles of p-nitrophenol released/g lens epithelium and maximum levels of lipid peroxidation (86.29 O.D./min/g lens epithelium. In contrast, mixed cataractous lens epithelium showed minimum activity of acid phosphatase (222.61 moles of p-nitrophenol released/g lens epithelium and minimum levels of lipid peroxidation (54.23 O.D./min/g lens epithelium. From our study, we correlated the maximum activity of acid phosphatase in mature cataractous lens epithelium with the increased areas of superimposed cells associated with the formation of mature cataract. Likewise, the maximum levels of lipid peroxidation in mature cataractous lens epithelium was correlated with increased permeability of the plasma membrane. Conversely, the minimum levels of lipid peroxidation in mixed cataractous lens epithelium makes us presume that factors other than lipid peroxidation may also account for the formation of mixed type of cataract.

  4. Protective Effects of Ferulic Acid on High Glucose-Induced Protein Glycation, Lipid Peroxidation, and Membrane Ion Pump Activity in Human Erythrocytes.

    Directory of Open Access Journals (Sweden)

    Weerachat Sompong

    Full Text Available Ferulic acid (FA is the ubiquitous phytochemical phenolic derivative of cinnamic acid. Experimental studies in diabetic models demonstrate that FA possesses multiple mechanisms of action associated with anti-hyperglycemic activity. The mechanism by which FA prevents diabetes-associated vascular damages remains unknown. The aim of study was to investigate the protective effects of FA on protein glycation, lipid peroxidation, membrane ion pump activity, and phosphatidylserine exposure in high glucose-exposed human erythrocytes. Our results demonstrated that FA (10-100 μM significantly reduced the levels of glycated hemoglobin (HbA1c whereas 0.1-100 μM concentrations inhibited lipid peroxidation in erythrocytes exposed to 45 mM glucose. This was associated with increased glucose consumption. High glucose treatment also caused a significant reduction in Na+/K+-ATPase activity in the erythrocyte plasma membrane which could be reversed by FA. Furthermore, we found that FA (0.1-100 μM prevented high glucose-induced phosphatidylserine exposure. These findings provide insights into a novel mechanism of FA for the prevention of vascular dysfunction associated with diabetes.

  5. High dietary level of synthetic vitamin E on lipid peroxidation, membrane fatty acid composition and cytotoxicity in breast cancer xenograft and in mouse host tissue

    Directory of Open Access Journals (Sweden)

    Barnes Christopher J

    2003-03-01

    Full Text Available Abstract Background d-α-tocopherol is a naturally occurring form of vitamin E not previously known to have antitumor activity. Synthetic vitamin E (sE is a commonly used dietary supplement consisting of a mixture of d-α-tocopherol and 7 equimolar stereoisomers. To test for antilipid peroxidation and for antitumor activity of sE supplementation, two groups of nude mice bearing a MDA-MB 231 human breast cancer tumor were fed an AIN-76 diet, one with and one without an additional 2000 IU/kg dry food (equivalent to 900 mg of all-rac-α-tocopherol or sE. This provided an intake of about 200 mg/kg body weight per day. The mice were killed at either 2 or 6 weeks after the start of dietary intervention. During necropsy, tumor and host tissues were excised for histology and for biochemical analyses. Results Tumor growth was significantly reduced by 6 weeks of sE supplementation. Thiobarbituric acid reactive substances, an indicator of lipid peroxidation, were suppressed in tumor and in host tissues in sE supplemented mice. In the sE treated mice, the fatty acid composition of microsomal and mitochondrial membranes of tumor and host tissues had proportionately less linoleic acid (n-6 C 18-2, similar levels of arachidonic acid (n-6 C 20-4, but more docosahexanoic acid (n-3 C 22-6. The sE supplementation had no significant effect on blood counts or on intestinal histology but gave some evidence of cardiac toxicity as judged by myocyte vacuoles and by an indicator of oxidative stress (increased ratio of Mn SOD mRNA over GPX1 mRNA. Conclusions At least one of the stereoisomers in sE has antitumor activity. Synthetic vitamin E appears to preferentially stabilize membrane fatty acids with more double bonds in the acyl chain. Although sE suppressed tumor growth and lipid peroxidation, it may have side-effects in the heart.

  6. Effect of Terminalia chebula fruit extract on lipid peroxidation and ...

    African Journals Online (AJOL)

    SERVER

    2007-08-20

    Aug 20, 2007 ... products mainly edible vegetables and spices, have a key role in chemopreventers ... protein; dunit/minute/mg protein ; eµg/mg protein; fn moles of H2O2 ... induce peroxidation of cell membrane lipids (Bhattacharya et al., 1999). .... catalase – like activities in seminal plasma and spermatozoa. Int. J. Androl.

  7. Lipid peroxidation and antioxidant enzymes in male infertility.

    Directory of Open Access Journals (Sweden)

    Dandekar S

    2002-07-01

    Full Text Available BACKGROUND AND AIM: Mammalian spermatozoa are rich in polyunsaturated fatty acids and are very susceptible to attack by reactive oxygen species (ROS and membrane lipid peroxide ion. Normally a balance is maintained between the amount of ROS produced and that scavenged. Cellular damage arises when this equilibrium is disturbed. A shift in the levels of ROS towards pro-oxidants in semen and vaginal secretions can induce an oxidative stress on spermatozoa. The aim was to study lipid peroxidation and antioxidant enzymes such as catalase, glutathione peroxidase and superoxide dismutase (SOD and to correlate the same, with the ′water test′, in male infertility. SETTINGS: Experimental study. SUBJECTS AND METHODS: Ejaculates from a total of 83 infertile and fertile healthy individuals were obtained. Lipid peroxidation and antioxidant enzyme levels were studied and correlated with water test. RESULTS: The results indicate that (i the antioxidant enzyme catalase showed no significant changes in the various pathological samples, (ii antioxidant enzymes SOD and glutathione peroxidase correlate positively with asthenozoospermic samples and (iii the degree of lipid peroxidation also correlates positively with the poorly swollen sperm tails. The increase in SOD and glutathione peroxidase values, in the pathological cases represents an attempt made to overcome the reactive oxygen species. CONCLUSION: Water test could be used as a preliminary marker test for sperm tail damage by reactive oxygen species, since it correlates very well with lipid peroxidation and antioxidant enzymes.

  8. Inhibition of radiation-induced lipid peroxidation by means of gallic polydisulphide

    International Nuclear Information System (INIS)

    Losev, Yu.P.; Amadyan, M.G.; Oganesyan, N.M.; Fedulov, A.S.; Abramyan, A.K.; Shagoyan, A.G.; Khachkavanktsyan, A.S.

    1999-01-01

    Inhibition of radiation-induced lipid peroxidation by means of gallic polydisulphade has been studied. Rats were exposed to X-rays in doses 4,8 and 5,25 Gy. Lipid peroxidation was analysed in blood plasma, membranes of erythrocytes and homogenates of liver and spleen tissues of rats. Polydisulphide of gallic acid was used as inhibitor of lipid peroxidation because of its effective antioxidant properties as have been reported previously. It has been demonstrated that gallic disulphide exhibited high inhibition efficiency in conditions of radiation-induced lipid peroxidation due to the effect of intra-molecular synergism

  9. Changes in mitochondrial function by lipid peroxidation and their inhibition by biscoclaurin alkaloid

    International Nuclear Information System (INIS)

    Aono, K.; Shiraishi, N.; Arita, T.; Inouye, B.; Nakazawa, T.; Utsumi, K.

    1981-01-01

    During in vitro investigation of changes in mitochondrial function accompanying lipid peroxidation, it was found that cepharanthine, a biscoclaurin alkaloid, protects against such change. Results obtained were as follows: (1) Fe2+ induces lipid peroxidation of isolated mitochondria, resulting in diminished oxidative phosphorylation. (2) This diminishment largely depends on deterioration of ion compartmentation of the membrane and an increase in latent ATPase activity. (3) The Fe2+-induced deterioration in ion compartmentation is inhibited by cepharanthine. (4) Cepharanthine inhibits the mitochondrial lipid peroxidation induced by Fe2+. (5) Cepharanthine inhibits the lipid peroxidation of soybean lecithin liposomes by 60Co-irradiation

  10. Ionizing radiation and lipid peroxidation in human body

    International Nuclear Information System (INIS)

    Giubileo, Gianfranco

    1997-07-01

    Lipids are organic compounds constituting the living cells. Lipid molecules can be disassembled through peroxidative pathways and hydrocarbons can be bred as end-product of lipid peroxidation in vivo. Lipid peroxidation can be started by an indirect effect of ionizing radiation. So a radioinduced cellular damage in human body can be detected by monitoring the production of specific hydrocarbons

  11. Differential sensitivity of cellular membranes to peroxidative processes

    International Nuclear Information System (INIS)

    Huijbers, W.A.R.

    1976-01-01

    A description is given of a morphological and cytochemical investigation into the effects of both vitamin E deficiency and X-irradiation on the ultrastructure and enzyme activities of several cellular membranes, particularly the plasma membrane and the membranes of lysosomes, mitochondria and endoplasmic reticulum. In the vitamin E deficient situation, the radicals and peroxides only originate near mitochondria and endoplasmic reticulum, so that these membrane systems suffer from changes. After irradiation of the liver of both the control duckling and the deficient duckling, radicals originate in all parts of the cell. Due to their high content of lipids and cholesterols, peroxides will occur mainly in plasma membranes and lysosomal membranes. Moreover, in these membranes there is hardly any protection by vitamin E

  12. [Correcting influence of vitamin E short chain derivatives on lipid peroxidation, liver cell membrane, and chromatin structure when rats are exposed to embichin].

    Science.gov (United States)

    Kovalenko, V M; Byshovets', T F; Hubs'kyĭ, Iu I; Levyts'kyĭ, Ie L; Shaiakhmetova, H M; Marchenko, O M; Voloshyna, O S; Saĭfetdinova, H A; Okhrimenko, V O; Donchenko, H V

    2000-01-01

    Embikhin causes activation of LPO processes in endoplasmic reticulum and in nuclear chromatine fractions of rat liver cells. The latter is accompanied by the impairment of repressive and active nuclear chromatine fractions structure. Derivate of vitamin E in these conditions renders correcting action on parameters of lipid peroxidation in the investigated subcellular structures, testifying its positive influence on the cell heredity apparatus state. The normalizing action of tocopherol derivative on cytochromes P450 and b5 levels is shown.

  13. Lipid Peroxidation: Pathophysiology and Pharmacological Implications in the Eye

    Directory of Open Access Journals (Sweden)

    Ya Fatou eNjie-Mbye

    2013-12-01

    Full Text Available Oxygen-derived free radicals such as hydroxyl and hydroperoxyl species have been shown to oxidize phospholipids and other membrane lipid components leading to lipid peroxidation. In the eye, lipid peroxidation has been reported to play an important role in degenerative ocular diseases (age-related macular degeneration, cataract, glaucoma, diabetic retinopathy. Indeed, ocular tissues are prone to damage from reactive oxygen species due to stress from constant exposure of the eye to sunlight, atmospheric oxygen and environmental chemicals. Furthermore, free radical catalyzed peroxidation of long chain polyunsaturated acids (LCPUFAs such as arachidonic acid and docosahexaenoic acid leads to generation of LCPUFA metabolites including isoprostanes and neuroprostanes that may further exert pharmacological/toxicological actions in ocular tissues. Evidence from literature supports the presence of endogenous defense mechanisms against reactive oxygen species in the eye, thereby presenting new avenues for the prevention and treatment of ocular degeneration. Hydrogen peroxide (H2O2 and synthetic peroxides can exert pharmacological and toxicological effects on tissues of the anterior uvea of several mammalian species. There is evidence suggesting that the retina, especially retinal ganglion cells can exhibit unique characteristics of antioxidant defense mechanisms. In the posterior segment of the eye, H2O2 and synthetic peroxides produce an inhibitory action on glutamate release (using [3H]-D-aspartate as a marker, in vitro and on the endogenous glutamate and glycine concentrations in vivo. In addition to peroxides, isoprostanes can elicit both excitatory and inhibitory effects on norepinephrine (NE release from sympathetic nerves in isolated mammalian iris ciliary bodies. Whereas isoprostanes attenuate dopamine release from mammalian neural retina, in vitro, these novel arachidonic acid metabolites exhibit a biphasic regulatory effect on glutamate release

  14. Probing lipid membrane electrostatics

    Science.gov (United States)

    Yang, Yi

    The electrostatic properties of lipid bilayer membranes play a significant role in many biological processes. Atomic force microscopy (AFM) is highly sensitive to membrane surface potential in electrolyte solutions. With fully characterized probe tips, AFM can perform quantitative electrostatic analysis of lipid membranes. Electrostatic interactions between Silicon nitride probes and supported zwitterionic dioleoylphosphatidylcholine (DOPC) bilayer with a variable fraction of anionic dioleoylphosphatidylserine (DOPS) were measured by AFM. Classical Gouy-Chapman theory was used to model the membrane electrostatics. The nonlinear Poisson-Boltzmann equation was numerically solved with finite element method to provide the potential distribution around the AFM tips. Theoretical tip-sample electrostatic interactions were calculated with the surface integral of both Maxwell and osmotic stress tensors on tip surface. The measured forces were interpreted with theoretical forces and the resulting surface charge densities of the membrane surfaces were in quantitative agreement with the Gouy-Chapman-Stern model of membrane charge regulation. It was demonstrated that the AFM can quantitatively detect membrane surface potential at a separation of several screening lengths, and that the AFM probe only perturbs the membrane surface potential by external field created by the internai membrane dipole moment. The analysis yields a dipole moment of 1.5 Debye per lipid with a dipole potential of +275 mV for supported DOPC membranes. This new ability to quantitatively measure the membrane dipole density in a noninvasive manner will be useful in identifying the biological effects of the dipole potential. Finally, heterogeneous model membranes were studied with fluid electric force microscopy (FEFM). Electrostatic mapping was demonstrated with 50 nm resolution. The capabilities of quantitative electrostatic measurement and lateral charge density mapping make AFM a unique and powerful

  15. Dual role of beta-carotene in combination with cigarette smoke aqueous extract on the formation of mutagenic lipid peroxidation products in lung membranes: dependence on pO2.

    Science.gov (United States)

    Palozza, P; Serini, S; Trombino, S; Lauriola, L; Ranelletti, F O; Calviello, G

    2006-12-01

    Results from some intervention trials indicated that supplemental beta-carotene enhanced lung cancer incidence and mortality in chronic smokers. The aim of this study was to verify the hypothesis that high concentrations of the carotenoid, under the pO2 present in lung (100-150 mmHg), may exert deleterious effects through a prooxidant mechanism. To test this hypothesis, we examined the interactions of beta-carotene and cigarette smoke condensate (tar) on the formation of lipid peroxidation products in rat lung microsomal membranes enriched in vitro with varying beta-carotene concentrations (from 1 to 10 nmol/mg prot) and then incubated with tar (6-25 microg/ml) under different pO2. As markers of lipid peroxidation, we evaluated the levels of conjugated dienes and malondialdehyde, possessing mutagenic and pro-carcinogenic activity. The exposure of microsomal membranes to tar induced a dose-dependent enhancement of lipid peroxidation, which progressively increased as a function of pO2. Under a low pO2 (15 mmHg), beta-carotene acted clearly as an antioxidant, inhibiting tar-induced lipid peroxidation. However, the carotenoid progressively lost its antioxidant efficiency by increasing pO2 (50-100 mmHg) and acted as a prooxidant at pO2 ranging from 100 to 760 mmHg in a dose-dependent manner. Consistent with this finding, the addition of alpha-tocopherol (25 microM) prevented the prooxidant effects of the carotenoid. beta-Carotene auto-oxidation, measured as formation of 5,6-epoxy-beta,beta-carotene, was faster at high than at low pO2 and the carotenoid was more rapidly consumed in the presence of tar. These data point out that the carotenoid may enhance cigarette smoke-induced oxidative stress and exert potential deleterious effects at the pO2 normally present in lung tissue.

  16. Blood lipid metabolites and meat lipid peroxidation responses of ...

    African Journals Online (AJOL)

    Esnart Mukumbo

    2017-06-19

    Jun 19, 2017 ... Fat and protein contents of thigh muscle and abdominal fat weight were measured and reported. Chickens fed LPO had greater serum triacylglycerol and very low ... favour lipid peroxidation, inhibit synthesis of higher homologous of ... The ambient temperature was gradually decreased from 33 °C at first.

  17. Blood lipid metabolites and meat lipid peroxidation responses of ...

    African Journals Online (AJOL)

    Blood samples were collected from broilers to evaluate serum biochemical metabolites on day 41. Thigh meat samples were provided and analysed after 1, 5 and 10 days' storage to evaluate lipid peroxidation at the end of the experiment. Fat and protein contents of thigh muscle and abdominal fat weight were measured ...

  18. Lipid Peroxidation and Antioxidant Status in Preeclampsia

    Directory of Open Access Journals (Sweden)

    Rokeya Begum

    2011-07-01

    Full Text Available Background: Preeclampsia is the most common and major medical complication of pregnancy with a high incidence of maternal and foetal morbidity and mortality. During pregnancy abnormally increased lipid peroxidation and free radical formation as well as significantly decreased antioxidants production in maternal blood may lead to pathogenesis of preeclampsia. So, we designed this study as little information is known about lipid peroxidation and antioxidant level in preeclampsia. Objectives: To assess the serum malondialdehyde (MDA level as a lipid peroxidation product and vitamin E (antioxidant level in women with preeclampsia as well as in normal pregnancy and to compare the values. Materials and Methods: The study was conducted on 60 women aged from 25 to 35 years in the department of Biochemistry, Budi Kemuliaan Maternity Hospital (BKMH in Jakarta during the period April to July 2004. Twenty were normal pregnant women and 20 were preeclamptic patients. For comparison age matched 20 apparently healthy nonpregnant women were included in the study. The study subjects were selected from outpatient department (OPD of Obstetrics and Gynaecology of BKMH in Jakarta. Serum MDA (lipid peroxidation product level was measured by thiobarbituric acid reactive substances assay (TBRAS method and vitamin E was estimated spectroflurometrically. Data were analyzed by unpaired Student’s t test between the groups by using SPSS version 12. Results: The mean serum MDA levels were significantly higher in normal pregnancy and also in preeclampsia than that of nonpregnant control group women (p<0.001. Again the serum MDA levels were significantly higher in preeclampsia than that of normal pregnant women (p<0.001. The serum vitamin E levels were significantly lower in preeclampsia and also in normal pregnancy than that of nonpregnant control women (p<0.001. Moreover, the serum vitamin E levels were significantly lower in preeclampsia compared to that of normal

  19. Combined effects of temperature and metal exposure on the fatty acid composition of cell membranes, antioxidant enzyme activities and lipid peroxidation in yellow perch (Perca flavescens)

    International Nuclear Information System (INIS)

    Fadhlaoui, Mariem; Couture, Patrice

    2016-01-01

    Highlights: • The fatty acid composition of yellow perch muscle at 9 °C was enhanced in monounsaturated and polyunsaturated fatty acids compared to fish maintained at 28 °C. • The thermal adjustment of muscle phospholipid fatty acid profiles is likely due to modifications of desaturase and elongase activities. • Exposure to Ni and Cd modified muscle phospholipid fatty acid composition in a temperature-dependent manner. • The higher fatty polyinsaturation in cold-acclimated fish did not increase their vulnerability to peroxidation. • Lower concentrations of malondialdehyde were measured in warm-acclimated, Ni-exposed fish, suggesting an overcompensation of antioxidant mechanisms that could explain their lower condition. - Abstract: The aim of this study was to investigate the combined effects of temperature and metal contamination (cadmium and nickel) on phospholipid fatty acid composition, antioxidant enzyme activities and lipid peroxidation in fish. Yellow perch were acclimated to two different temperatures (9 °C and 28 °C) and exposed either to Cd or Ni (respectively 4 μg/L and 600 μg/L) for seven weeks. Superoxide dismutase, catalase, glutathione-S-transferase, glutathione peroxidase activities and glutathione concentration were measured as indicators of antioxidant capacities, while malondialdehyde concentration was used as an indicator of lipid peroxidation. Poikilotherms including fish counteract the effects of temperature on phospholipid fatty acid ordering by remodelling their composition to maintain optimal fluidity. Accordingly, in our study, the fatty acid composition of yellow perch muscle at 9 °C was enhanced in monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA) compared to fish maintained at 28 °C, in agreement with the theory of homeoviscous adaptation. Using ratios of various fatty acids as surrogates for desaturase and elongase activities, our data suggests that modification of the activity of these enzymes is

  20. Combined effects of temperature and metal exposure on the fatty acid composition of cell membranes, antioxidant enzyme activities and lipid peroxidation in yellow perch (Perca flavescens)

    Energy Technology Data Exchange (ETDEWEB)

    Fadhlaoui, Mariem; Couture, Patrice, E-mail: patrice.couture@ete.inrs.ca

    2016-11-15

    Highlights: • The fatty acid composition of yellow perch muscle at 9 °C was enhanced in monounsaturated and polyunsaturated fatty acids compared to fish maintained at 28 °C. • The thermal adjustment of muscle phospholipid fatty acid profiles is likely due to modifications of desaturase and elongase activities. • Exposure to Ni and Cd modified muscle phospholipid fatty acid composition in a temperature-dependent manner. • The higher fatty polyinsaturation in cold-acclimated fish did not increase their vulnerability to peroxidation. • Lower concentrations of malondialdehyde were measured in warm-acclimated, Ni-exposed fish, suggesting an overcompensation of antioxidant mechanisms that could explain their lower condition. - Abstract: The aim of this study was to investigate the combined effects of temperature and metal contamination (cadmium and nickel) on phospholipid fatty acid composition, antioxidant enzyme activities and lipid peroxidation in fish. Yellow perch were acclimated to two different temperatures (9 °C and 28 °C) and exposed either to Cd or Ni (respectively 4 μg/L and 600 μg/L) for seven weeks. Superoxide dismutase, catalase, glutathione-S-transferase, glutathione peroxidase activities and glutathione concentration were measured as indicators of antioxidant capacities, while malondialdehyde concentration was used as an indicator of lipid peroxidation. Poikilotherms including fish counteract the effects of temperature on phospholipid fatty acid ordering by remodelling their composition to maintain optimal fluidity. Accordingly, in our study, the fatty acid composition of yellow perch muscle at 9 °C was enhanced in monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA) compared to fish maintained at 28 °C, in agreement with the theory of homeoviscous adaptation. Using ratios of various fatty acids as surrogates for desaturase and elongase activities, our data suggests that modification of the activity of these enzymes is

  1. Sperm DNA damage in relation to lipid peroxidation following freezing-thawing of boar semen

    OpenAIRE

    Fraser, L.; Strzeżek, J.; Wasilewska, K.; Pareek, C.S.

    2017-01-01

    This study investigated the relationships between lipid peroxidation (LPO) and sperm DNA damage following freezing-thawing of boar semen in different extenders. The comet assay was used to measure the extent of sperm DNA damage in a cryoprotectant-free extender or in cryoprotectant-based extenders after single and repeated freezing and thawing. As well as an analysis of sperm motion characteristics, mitochondrial function, membrane integrity, and lipid peroxidation (LPO) were assessed simulta...

  2. A survey of chemicals inducing lipid peroxidation in biological systems.

    Science.gov (United States)

    Kappus, H

    1987-01-01

    A great number of drugs and chemicals are reviewed which have been shown to stimulate lipid peroxidation in any biological system. The underlying mechanisms, as far as known, are also dealt with. Lipid peroxidation induced by iron ions, organic hydroperoxides, halogenated hydrocarbons, redox cycling drugs, glutathione depleting chemicals, ethanol, heavy metals, ozone, nitrogen dioxide and a number of miscellaneous compounds, e.g. hydrazines, pesticides, antibiotics, are mentioned. It is shown that lipid peroxidation is stimulated by many of these compounds. However, quantitative estimates cannot be given yet and it is still impossible to judge the biological relevance of chemical-induced lipid peroxidation.

  3. Antioxidant effect of bisphosphonates and simvastatin on chondrocyte lipid peroxidation

    International Nuclear Information System (INIS)

    Dombrecht, E.J.; De Tollenaere, C.B.; Aerts, K.; Cos, P.; Schuerwegh, A.J.; Bridts, C.H.; Van Offel, J.F.; Ebo, D.G.; Stevens, W.J.; De Clerck, L.S.

    2006-01-01

    The objective of this study was to evaluate the effect of bisphosphonates (BPs) and simvastatin on chondrocyte lipid peroxidation. For this purpose, a flow cytometrical method using C11-BODIPY 581/591 was developed to detect hydroperoxide-induced lipid peroxidation in chondrocytes. Tertiary butylhydroperoxide (t-BHP) induced a time and concentration dependent increase in chondrocyte lipid peroxidation. Addition of a Fe 2+ /EDTA complex to t-BHP or hydrogen peroxide (H 2 O 2 ) clearly enhanced lipid peroxidation. The lipophilic simvastatin demonstrated a small inhibition in the chondrocyte lipid peroxidation. None of three tested BPs (clodronate, pamidronate, and risedronate) had an effect on chondrocyte lipid peroxidation induced by t-BHP. However, when Fe 2+ /EDTA complex was added to t-BHP or H 2 O 2 , BPs inhibited the lipid peroxidation process varying from 25% to 58%. This study demonstrates that BPs have antioxidant properties as iron chelators, thereby inhibiting the chondrocyte lipid peroxidation. These findings add evidence to the therapeutic potential of bisphosphonates and statins in rheumatoid arthritis

  4. Effect of cadmium chloride on hepatic lipid peroxidation in mice

    DEFF Research Database (Denmark)

    Andersen, H R; Andersen, O

    1988-01-01

    Intraperitoneal administration of cadmium chloride to 8-12 weeks old CBA-mice enhanced hepatic lipid peroxidation. A positive correlation between cadmium chloride dose and level of peroxidation was observed in both male and female mice. A sex-related difference in mortality was not observed...... but at a dose of 25 mumol CdCl2/kg the level of hepatic lipid peroxidation was higher in male mice than in female mice. The hepatic lipid peroxidation was not increased above the control level in 3 weeks old mice, while 6 weeks old mice responded with increased peroxidation as did 8-12 weeks old mice....... The mortality after an acute toxic dose of cadmium chloride was the same in the three age groups. Pretreatment of mice with several low intraperitoneal doses of cadmium chloride alleviated cadmium induced mortality and lipid peroxidation. The results demonstrate both age dependency and a protective effect...

  5. Lipid peroxidation and ascorbic acid levels in Nigeria children with ...

    African Journals Online (AJOL)

    This study was undertaken to establish data on the roles of lipid peroxidation and ascorbic acid in the pathology of malaria in Nigeria children. We measured the levels of malondialdehyde (MDA), a marker of lipid peroxidation and ascorbic acid in the plasma of 406 parasitaemic and 212 non-parasitaemic Nigerian children.

  6. Plasma lipid peroxidation and progression of disability in multiple sclerosis

    NARCIS (Netherlands)

    Koch, M.; Mostert, J.; Arutjunyan, A. V.; Stepanov, M.; Teelken, A.; Heersema, D.; De Keyser, J.

    Oxidative stress has been implicated in the pathophysiology of multiple sclerosis (MS), but its relation to disease progression is uncertain. To evaluate the relationship of plasma lipid peroxidation with progression of disability in MS, we measured blood plasma fluorescent lipid peroxidation

  7. Analysis of lipid peroxidation kinetics. I

    DEFF Research Database (Denmark)

    Doktorov, Alexander B.; Lukzen, Nikita N.; Pedersen, Jørgen Boiden

    2008-01-01

    concentrations of reactants or different ways of initiating the re-  action. Nor has it been possible to predict the time dependence of the  products. The reason for these problems is the complicated structure  of the kinetic scheme, which includes a chain reaction. In this work  we perform an in depth analysis......  The kinetics of the lipid peroxidation reaction is only partly under-  stood. Although the set of reactions constituting the overall reaction  is believed to be known, it has not been possible to predict how the  reaction will respond to a change of one or more of the parameters, e.g.  initial...... of the importance of the individual  reaction steps and we introduce a new quasi-stationary concentration  method based on the assumption that one or more concentrations vary  much slower than the others. We show that it is justified to use a  quasi-stationary concentration approximation for the alkyl radical L...

  8. the effects of vitamin e supplementation on serum lipid peroxidation ...

    African Journals Online (AJOL)

    DR. C.O.NWAIGWE

    The effects of dietary supplementation of vitamin E on feed intake and serum lipid peroxidation formation were ... belongs to the family Birnaviridae and of the genus Birnavirus ... diseases, Alzheimer's disease and increased resistance to ...

  9. Lysosomal degradation of membrane lipids.

    Science.gov (United States)

    Kolter, Thomas; Sandhoff, Konrad

    2010-05-03

    The constitutive degradation of membrane components takes place in the acidic compartments of a cell, the endosomes and lysosomes. Sites of lipid degradation are intralysosomal membranes that are formed in endosomes, where the lipid composition is adjusted for degradation. Cholesterol is sorted out of the inner membranes, their content in bis(monoacylglycero)phosphate increases, and, most likely, sphingomyelin is degraded to ceramide. Together with endosomal and lysosomal lipid-binding proteins, the Niemann-Pick disease, type C2-protein, the GM2-activator, and the saposins sap-A, -B, -C, and -D, a suitable membrane lipid composition is required for degradation of complex lipids by hydrolytic enzymes. Copyright 2009 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  10. Lipids and membrane lateral organization

    Directory of Open Access Journals (Sweden)

    Sandro eSonnino

    2010-11-01

    Full Text Available Shortly after the elucidation of the very basic structure and properties of cellular membranes, it became evident that cellular membranes are highly organized structures with multiple and multi-dimensional levels of order. Very early observations suggested that the lipid components of biological membranes might be active players in the creations of these levels of order. In the late 80’s, several different and diverse experimental pieces of evidence coalesced together giving rise to the lipid raft hypothesis. Lipid rafts became enormously (and, in the opinion of these authors, sometimes acritically popular, surprisingly not just within the lipidologist community (who is supposed to be naturally sensitive to the fascination of lipid rafts. Today, a PubMed search using the key word lipid rafts returned a list of 3767 papers, including 690 reviews (as a term of comparison, searching over the same time span for a very hot lipid-related key word, ceramide returned 6187 hits with 799 reviews, and a tremendous number of different cellular functions have been described as lipid raft-dependent. However, a clear consensus definition of lipid raft has been proposed only in recent times, and the basic properties, the ruling forces, and even the existence of lipid rafts in living cells have been recently matter of intense debate. The scenario that is gradually emerging from the controversies elicited by the lipid raft hypothesis emphasize multiple roles for membrane lipids in determining membrane order, that encompasses their tendency to phase separation but are clearly not limited to this. In this review, we would like to re-focus the attention of the readers on the importance of lipids in organizing the fine structure of cellular membranes.

  11. A chemiluminescent method for determination of lipid peroxidation

    International Nuclear Information System (INIS)

    Liang Xiaofeng; Hu Tianxi; Fan Xiaobing

    2003-01-01

    We established a chemiluminescent system for determination of lipid peroxidation and screening anti-oxidants. The lipid containing unsaturated fatly acids was injected into a galls tube. Luminol solution and the deionized water were added into it too. The glass tube was put into a preincubation box to incubate it for 0.5 h at 37 degree C. AAPH solution was injected into the tube for immediate measurement in a biochemiluminometer at 38-39 degree C. The pulses /6s(CP6s) were determined with T-2 program. Chemiluminescent dynamic and lipid peroxidation changes were observed continuously. Once the CL intensity of lipid peroxidation got peak, the antioxidant which has different concentration was added immediately in situ. A certain CL intensity (CP6s) was chosen as evaluation index to compare the activity of antioxidants. A luminol chemiluminescent system for determination of lipid peroxidation has been made. It was found that Vit. C, teapolyphenol, and glutathione have effects on scavenging lipid free radicals. The new method is quick, sensitive, and simple for determination of lipid peroxidation and screening antioxidants

  12. Oxalomalate, a competitive inhibitor of NADP+ -dependent isocitrate dehydrogenase, regulates lipid peroxidation-mediated apoptosis in U937 cells.

    Science.gov (United States)

    Yang, Eun Sun; Yang, Joon-Hyuck; Park, Ji Eun; Park, Jeen-Woo

    2005-01-01

    Membrane lipid peroxidation processes yield products that may react with DNA and proteins to cause oxidative modifications. Recently, we demonstrated that the control of cytosolic redox balance and the cellular defense against oxidative damage is one of the primary functions of cytosolic NADP+ -dependent isocitrate dehydrogenase (IDPc) through to supply NADPH for antioxidant systems. The protective role of IDPc against lipid peroxidation-mediated apoptosis in U937 cells was investigated in control and cells pre-treated with oxlalomalate, a competitive inhibitor of IDPc. Upon exposure to 2,2'-azobis (2-amidinopropane) hydrochloride (AAPH) to U937 cells, which induces lipid peroxidation in membranes, the susceptibility to apoptosis was higher in oxalomalate-treated cells as compared to control cells. The results suggest that IDPc plays an important protective role in apoptosis of U937 cells induced by lipid peroxidation-mediated oxidative stress.

  13. Sensing voltage across lipid membranes

    Science.gov (United States)

    Swartz, Kenton J.

    2009-01-01

    The detection of electrical potentials across lipid bilayers by specialized membrane proteins is required for many fundamental cellular processes such as the generation and propagation of nerve impulses. These membrane proteins possess modular voltage-sensing domains, a notable example being the S1-S4 domains of voltage-activated ion channels. Ground-breaking structural studies on these domains explain how voltage sensors are designed and reveal important interactions with the surrounding lipid membrane. Although further structures are needed to fully understand the conformational changes that occur during voltage sensing, the available data help to frame several key concepts that are fundamental to the mechanism of voltage sensing. PMID:19092925

  14. Aluminum induces lipid peroxidation and aggregation of human blood platelets

    Directory of Open Access Journals (Sweden)

    T.J.C. Neiva

    1997-05-01

    Full Text Available Aluminum (Al3+ intoxication is thought to play a major role in the development of Alzheimer's disease and in certain pathologic manifestations arising from long-term hemodialysis. Although the metal does not present redox capacity, it can stimulate tissue lipid peroxidation in animal models. Furthermore, in vitro studies have revealed that the fluoroaluminate complex induces diacylglycerol formation, 43-kDa protein phosphorylation and aggregation. Based on these observations, we postulated that Al3+-induced blood platelet aggregation was mediated by lipid peroxidation. Using chemiluminescence (CL of luminol as an index of total lipid peroxidation capacity, we established a correlation between lipid peroxidation capacity and platelet aggregation. Al3+ (20-100 µM stimulated CL production by human blood platelets as well as their aggregation. Incubation of the platelets with the antioxidants nor-dihydroguaiaretic acid (NDGA (100 µM and n-propyl gallate (NPG (100 µM, inhibitors of the lipoxygenase pathway, completely prevented CL and platelet aggregation. Acetyl salicylic acid (ASA (100 µM, an inhibitor of the cyclooxygenase pathway, was a weaker inhibitor of both events. These findings suggest that Al3+ stimulates lipid peroxidation and the lipoxygenase pathway in human blood platelets thereby causing their aggregation

  15. Mechanics of Lipid Bilayer Membranes

    Science.gov (United States)

    Powers, Thomas R.

    All cells have membranes. The plasma membrane encapsulates the cell's interior, acting as a barrier against the outside world. In cells with nuclei (eukaryotic cells), membranes also form internal compartments (organelles) which carry out specialized tasks, such as protein modification and sorting in the case of the Golgi apparatus, and ATP production in the case of mitochondria. The main components of membranes are lipids and proteins. The proteins can be channels, carriers, receptors, catalysts, signaling molecules, or structural elements, and typically contribute a substantial fraction of the total membrane dry weight. The equilibrium properties of pure lipid membranes are relatively well-understood, and will be the main focus of this article. The framework of elasticity theory and statistical mechanics that we will develop will serve as the foundation for understanding biological phenomena such as the nonequilibrium behavior of membranes laden with ion pumps, the role of membrane elasticity in ion channel gating, and the dynamics of vesicle fission and fusion. Understanding the mechanics of lipid membranes is also important for drug encapsulation and delivery.

  16. Relationship Between Calorie Restriction, Lipid Peroxidation ...

    African Journals Online (AJOL)

    In the brain of the caloric restricted rats, there was little or no change in the tGSH and GSH, although the GSSG and GSSG/GSH% ratio were increased significantly. These results suggest that aging of rats had been decelerated by caloric restriction due to the decrease in the peroxidative damage in the lungs and brain.

  17. Radiation effect on lipid peroxide content of spices

    International Nuclear Information System (INIS)

    Kaneko, Nobutada; Ito, Hitoshi; Ishigaki, Isao

    1990-01-01

    To evaluate the radiation-induced deterioration of lipid in spices, peroxide value, iodine value and acid value were measured after extraction by chloroform. Peroxide values of black pepper and white pepper were not increased by gamma-irradiation with doses below 30 kGy and gradually increased at higher dose up to 80 kGy in this study. On contrary, peroxide values of clove and rosemary increased rather quickly below 20 kGy of gamma-irradiation, and they became stationary at higher dose. Iodine values and acid values had relationship with peroxide values on each kind of spices. On the storage study of irradiated spices, peroxide values decreased quickly during 20 days storage as same as nonirradiated spices, and it became stationary after 20 to 50 days storage at 30degC. Enhancement of oxidized deterioration were not observed even higher irradiation doses up to 80 kGy in this study. (author)

  18. Ameliorating effects of genestein: Study on mice liver glutathione and lipid peroxidation after irradiation

    International Nuclear Information System (INIS)

    Gaur, A.

    2010-01-01

    Genistein is a soya isoflavone, which is found naturally in legumes. such as soybeans and chickpeas. Radiation-induced free radicals in turn impair the antioxidative defense mechanism, leading to an increased membrane lipid peroxidation that results in damage of the membrane bound enzyme and may lead to damage or death of cell. Hence, the lipid peroxidation is a good biomarker of damage occurs due to radiation and the inhibition of lipid peroxidation is suggestive of radioprotective action. Glutathione has been shown to protect cells against oxidative stress by reacting with peroxides and hydroperoxides and determines the inherent radiosensitivity of cells. Materials and Methods: For experimentation, healthy Swiss Albino male mice of 6-8 weeks old were selected from inbred colony. Genistein was dissolved in dimethyl sulfoxide and then prepared different concentration solutions so that the volume administered intraperitoneally was 0.5 ml. Lipid peroxidation was estimated by the method of Ohkawa and GSH was estimated by the method of Moron. Results: The intraperitoneal administration of optimum dose (200 mg/kg body weight) of Genistein before 24 hours and 15 minutes of irradiation (8 Gy at a dose rate of 1.02 Gy/min)reverted the increase in lipid peroxidation (by 18.01% ± 3.05) and decrease of Glutathione (by 62.05%±21.58) caused by irradiation in liver of Swiss albino mice. Statistically analyzed survival data produced a dose reduction factor = 1.24. Conclusion: The results indicate that Genistein against radiation effect may pave way to the formulation of medicine in radiotherapy for normal tissue and possible against radiomimetic drug induced toxicity.

  19. Dietary fiber and lipid peroxidation: effect of dietary fiber on levels of lipids and lipid peroxides in high fat diet.

    Science.gov (United States)

    Thampi, B S; Manoj, G; Leelamma, S; Menon, V P

    1991-06-01

    Effect of feeding coconut and blackgram fiber isolated as neutral detergent fiber (NDF) on the levels of lipids and lipid peroxides was studied in rats given a high fat diet. Concentration of cholesterol, free falty acid and phospholipids showed significant decrease in the serum, liver aorta and intestine of coconut and blackgram fiber groups. Concentration of malondialdehyde (MDA) and conjugated dienes was significantly decreased in liver and intestine of both fiber groups, while hydroperoxides showed significant increase in liver and heart of both the fiber groups. SOD and catalase activity was found to be increased in liver, intestine, heart proximal colon and distal colon of both the fiber groups. Serum ceruloplasmin levels showed a slight increase in animals fed coconut and blackgram fiber groups. Glutathione levels in liver, intestine proximal colon, distal colon and heart also showed a significant decrease in the animals of both the fiber groups.

  20. Possible involvement of membrane lipids peroxidation and oxidation of catalytically essential thiols of the cerebral transmembrane sodium pump as component mechanisms of iron-mediated oxidative stress-linked dysfunction of the pump's activity

    Directory of Open Access Journals (Sweden)

    T.I. Omotayo

    2015-04-01

    Full Text Available The precise molecular events defining the complex role of oxidative stress in the inactivation of the cerebral sodium pump in radical-induced neurodegenerative diseases is yet to be fully clarified and thus still open. Herein we investigated the modulation of the activity of the cerebral transmembrane electrogenic enzyme in Fe2+-mediated in vitro oxidative stress model. The results show that Fe2+ inhibited the transmembrane enzyme in a concentration dependent manner and this effect was accompanied by a biphasic generation of aldehydic product of lipid peroxidation. While dithiothreitol prevented both Fe2+ inhibitory effect on the pump and lipid peroxidation, vitamin E prevented only lipid peroxidation but not inhibition of the pump. Besides, malondialdehyde (MDA inhibited the pump by a mechanism not related to oxidation of its critical thiols. Apparently, the low activity of the pump in degenerative diseases mediated by Fe2+ may involve complex multi-component mechanisms which may partly involve an initial oxidation of the critical thiols of the enzyme directly mediated by Fe2+ and during severe progression of such diseases; aldehydic products of lipid peroxidation such as MDA may further exacerbate this inhibitory effect by a mechanism that is likely not related to the oxidation of the catalytically essential thiols of the ouabain-sensitive cerebral electrogenic pump.

  1. The results of the lipids peroxidation products on the DNA bases as biological markers of the oxidative stress

    International Nuclear Information System (INIS)

    Falletti, O.

    2007-10-01

    Different ways of DNA damages have been studied, among these ones the direct way of DNA damages formation by the reactive oxygen species (R.O.S.). This way leads to the formation of oxidative DNA damages. In 1990, works have suggested an indirect way of DNA damages formation, the lipids peroxidation. Instead of oxidizing directly DNA, the R.O.S. oxide the lipids present in the cells and their membranes; The products coming from this degradation are able to provoke DNA damages. This way has not been studied very much. The work of this thesis is axed on this DNA theme and lipids peroxidation. In the first chapter, we begin by presenting DNA and the direct way of oxidative damages formation by the R.O.S.Then, we speak about the cell lipids suffering oxidation reactions and the different ways of lipids oxidation. Then, we present how the lipid peroxidation is a source of damages for DNA. (N.C.)

  2. Effect of irradiation of lipid peroxidation in serum, 2

    International Nuclear Information System (INIS)

    Haisa, Yoshio

    1976-01-01

    With blood obtained from patients irradiated for cervical uterine cancer (consisting of 4 cases of Stage I, 5 cases of Stage II and 4 cases of Stage III), changes of blood picture, serum lipid weight and serum lipid peroxide accompanying irradiation were studied on 3 occasions, before, during and after the irradiation. The following results were obtained. Serum lipid and serum lipid peroxide were found to increase along with the advance of uterine cancer from Stage I to II and III. At the termination of irradiation the serum lipid and serum lipid peroxide in the cases of cervical uterine cancer at Stage III were found to have recovered to close to the levels before irradiation, but in the other cases these values tended to increase with irradiation. Except the termination of irradiation treatment of cervical uterine cancer of Stage III, the decrease of leucocyte count has a mutual relationship with the increase of serum thiobarbituric acid (TBA), so that change in the serum TBA level can be assumed to be a criterion for irradiation injury. (auth.)

  3. Lipid peroxidation and cytotoxicity induced by respirable volcanic ash

    Energy Technology Data Exchange (ETDEWEB)

    Cervini-Silva, Javiera, E-mail: jcervini@correo.cua.uam.mx [Departamento de Procesos y Tecnología, Universidad Autónoma Metropolitana Unidad Cuajimalpa, México City (Mexico); Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA (United States); Nieto-Camacho, Antonio [Laboratorio de Pruebas Biológicas, Instituto de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, México City (Mexico); Gomez-Vidales, Virginia [Laboratorio de Resonancia Paramagnética Electrónica, Instituto de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, México City (Mexico); Ramirez-Apan, María Teresa [Laboratorio de Pruebas Biológicas, Instituto de Química, Universidad Nacional Autónoma de México, Ciudad Universitaria, México City (Mexico); Palacios, Eduardo; Montoya, Ascención [Dirección de Investigación y Posgrado, Instituto Mexicano del Petróleo (Mexico); Kaufhold, Stephan [BGR Bundesansaltfür Geowissenschaften und Rohstoffe, Stilleweg 2, D-30655 Hannover (Germany); and others

    2014-06-01

    Highlights: • Respirable volcanic ash induces oxidative degradation of lipids in cell membranes. • Respirable volcanic ash triggers cytotoxicity in murin monocyle/macrophage cells. • Oxidative stress is surface controlled but not restricted by surface- Fe{sup 3+}. • Surface Fe{sup 3+} acts as a stronger inductor in allophanes vs phyllosilicates or oxides. • Registered cell-viability values were as low as 68.5 ± 6.7%. - Abstract: This paper reports that the main component of respirable volcanic ash, allophane, induces lipid peroxidation (LP), the oxidative degradation of lipids in cell membranes, and cytotoxicity in murin monocyle/macrophage cells. Naturally-occurring allophane collected from New Zealand, Japan, and Ecuador was studied. The quantification of LP was conducted using the Thiobarbituric Acid Reactive Substances (TBARS) assay. The cytotoxic effect was determined by the 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide colorimetric assay. Electron-Paramagnetic Resonance (EPR) determinations of naturally-occurring allophane confirmed the incorporation in the structure and clustering of structural Fe{sup 3+}, and nucleation and growth of small-sized Fe (oxyhydr)oxide or gibbsite. LP induced by allophane varied with time, and solid concentration and composition, reaching 6.7 ± 0.2 nmol TBARS mg prot{sup −1}. LP was surface controlled but not restricted by structural or surface-bound Fe{sup 3+}, because redox processes induced by soluble components other than perferryl iron. The reactivity of Fe{sup 3+} soluble species stemming from surface-bound Fe{sup 3+} or small-sized Fe{sup 3+} refractory minerals in allophane surpassed that of structural Fe{sup 3+} located in tetrahedral or octahedral sites of phyllosilicates or bulk iron oxides. Desferrioxamine B mesylate salt (DFOB) or ethylenediaminetetraacetic acid (EDTA) inhibited LP. EDTA acted as a more effective inhibitor, explained by multiple electron transfer pathways. Registered cell

  4. The effects of beta-carotene and vitamin E on erythrocytes lipid peroxidation in beta-thalassemia patients

    Directory of Open Access Journals (Sweden)

    Soleiman Mahjoub

    2007-12-01

    Full Text Available BACKGROUND: Thalassemia is the most common hereditary disease in the world. Thalassemic erythrocytes are exposed to higher oxidative stress and lipid peroxidation. The aim of this study was to investigate the effects of beta-carotene and vitamin E on erythrocytes lipid peroxidation in beta-thalassemia patients.
    METHODS: A prospective double-blind, placebo-controlled study of the effect of beta-carotene and vitamin E on lipid peroxidation in erythrocytes membranes was performed on 120 beta-thalassemia major patients in four groups. The patients were supplemented for 4 weeks as follows: group 1 with beta-carotene (13 mg/day, group 2 with vitamin E (550 mg/day, group 3 with beta-carotene plus vitamin E and group 4 with placebo. We prepared all capsules for 4 roups in the same shape and color. Measurements of serum beta-carotene and vitamin E were performed by high performance
    liquid chromatography. After preparation of ghost cells from blood specimens, malondialdehyde (MDA was determined as index of lipid peroxidation in erythrocytes membranes before and after treatment. RESULTS: The levels of serum beta-carotene and vitamin E were significantly lower and MDA concentrations in erythrocytes membranes were significantly higher in beta-thalassemia patients compared to controls (P<0.001. In groups that treated with vitamin supplements for 4-weeks, lipid peroxidation rates were significantly reduced after treatment (P<0.001, but in placebo group there was not significant difference (P>0.05.
    CONCLUSIONS: Our findings provide evidence that an oral treatment with beta-carotene and vitamin E can significantly reduce lipid peroxidation of erythrocytes membranes and could be useful in management of beta-thalassemia major patients. KEYWORDS: Beta-thalassemia major, beta-carotene, vitamin E, malondialdehyde, lipid peroxidation.

  5. Combined effect of vanadium and nickel on lipid peroxidation and ...

    African Journals Online (AJOL)

    The exposure to nickel led to a significant decrease (p < 0.001) in SOD, GST activities in liver and GSH content in kidney and a significant (p < 0.001) increase in the hepatic MDA content and renal SOD activity. When the metals were administered in combination, the elevation of lipid peroxidation did not potentiate. However ...

  6. Sperm DNA damage in relation to lipid peroxidation following ...

    African Journals Online (AJOL)

    This study investigated the relationships between lipid peroxidation (LPO) and sperm DNA damage following freezing-thawing of boar semen in different extenders. The comet assay was used to measure the extent of sperm DNA damage in a cryoprotectant-free extender or in cryoprotectant-based extenders after single ...

  7. Plasma Lipid Peroxidation and Total Antioxidant Status among ...

    African Journals Online (AJOL)

    BACKGROUND: The oxidative modification hypothesis of atherosclerosis predicts that low density lipoprotein-cholesterol (LDL-C) oxidation is an early event in atherosclerosis and that oxidized LDL-C contributes to atherogenesis. OBJECTIVE: To determine a link, if any, between the plasma lipid peroxidation and total ...

  8. Desiccation-induced changes in viability, lipid peroxidation and ...

    African Journals Online (AJOL)

    user

    2012-05-31

    May 31, 2012 ... Key words: Intermediate seeds, desiccation, reactive oxygen species, antioxidant enzymes, lipid peroxidation,. Mimusops ... between ROS production and cell defenses determines ... needed for reduction of dehydroascorbate, which is .... was calculated using the extinction coefficient (6.2 mM-1cm-1) for.

  9. Iron release from ferritin and lipid peroxidation by radiolytically generated reducing radicals

    International Nuclear Information System (INIS)

    Reif, D.W.; Schubert, J.; Aust, S.D.

    1988-01-01

    Iron is involved in the formation of oxidants capable of damaging membranes, protein, and DNA. Using 137 Cs gamma radiation, we investigated the release of iron from ferritin and concomitant lipid peroxidation by radiolytically generated reducing radicals, superoxide and the carbon dioxide anion radical. Both radicals released iron from ferritin with similar efficiencies and iron mobilization from ferritin required an iron chelator. Radiolytically generated superoxide anion resulted in peroxidation of phospholipid liposomes as measured by malondialdehyde formation only when ferritin was included as an iron source and the released iron was found to be chelated by the phospholipid liposomes

  10. LIPID PEROXIDATION AND JOB STRESS IN DENTAL HEALTHCARE WORKERS

    Directory of Open Access Journals (Sweden)

    S. V. Melnikova

    2014-04-01

    Full Text Available This study devoted to the lipid peroxidation indices in dentists target group as a marker of psycho-emotional state. We revealed increase in the level of TBA-active products in female and male dentists during job stress. There was strong decrease in level of TBA-active products in control group of dentist that study during the lectures. Activation of lipid peroxidation in dentists during dentist examination can be considered as non-specific component of reactions towards the stressors of professional activities. We also revealed that the initial level of TBA-active products in female and male dentists before the outpatient dental reception was higher than that of dentists that study before lectures. This is indicates the mobilization of sympathetic nervous system before beginning of the working day. The contents of the level of TBA-active products in the oral fluid of female and male dentists after dental examination significantly increased, whereas these indices decreased in the group of dentists that study after the lectures. The increasing of TBA-active products in dentists after outpatient dental reception was by 42.5 % and 77 % higher compared with a group of dentists that study in the lecture classes. The results of correlation analysis suggest the influence of lipid peroxidation processes on the cardiovascular and blood system of dentists during job stress. Activation of lipid peroxidation in dentists during dental examination can be considered as non-specific component of the body's response to stressors influence in professional activities. Key words: dentists, activation of lipid peroxidation, psychoemotional stress, job stress.

  11. Quality control of photosystem II: lipid peroxidation accelerates photoinhibition under excessive illumination.

    Directory of Open Access Journals (Sweden)

    Tiffanie Chan

    Full Text Available Environmental stresses lower the efficiency of photosynthesis and sometimes cause irreversible damage to plant functions. When spinach thylakoids and Photosystem II membranes were illuminated with excessive visible light (100-1,000 µmol photons m(-1 s(-1 for 10 min at either 20°C or 30°C, the optimum quantum yield of Photosystem II decreased as the light intensity and temperature increased. Reactive oxygen species and endogenous cationic radicals produced through a photochemical reaction at and/or near the reaction center have been implicated in the damage to the D1 protein. Here we present evidence that lipid peroxidation induced by the illumination is involved in the damage to the D1 protein and the subunits of the light-harvesting complex of Photosystem II. This is reasoned from the results that considerable lipid peroxidation occurred in the thylakoids in the light, and that lipoxygenase externally added in the dark induced inhibition of Photosystem II activity in the thylakoids, production of singlet oxygen, which was monitored by electron paramagnetic resonance spin trapping, and damage to the D1 protein, in parallel with lipid peroxidation. Modification of the subunits of the light-harvesting complex of Photosystem II by malondialdehyde as well as oxidation of the subunits was also observed. We suggest that mainly singlet oxygen formed through lipid peroxidation under light stress participates in damaging the Photosystem II subunits.

  12. Assay to detect lipid peroxidation upon exposure to nanoparticles.

    Science.gov (United States)

    Potter, Timothy M; Neun, Barry W; Stern, Stephan T

    2011-01-01

    This chapter describes a method for the analysis of human hepatocarcinoma cells (HEP G2) for lipid peroxidation products, such as malondialdehyde (MDA), following treatment with nanoparticle formulations. Oxidative stress has been identified as a likely mechanism of nanoparticle toxicity, and cell-based in vitro systems for evaluation of nanoparticle-induced oxidative stress are widely considered to be an important component of biocompatibility screens. The products of lipid peroxidation, lipid hydroperoxides, and aldehydes, such as MDA, can be measured via a thiobarbituric acid reactive substances (TBARS) assay. In this assay, which can be performed in cell culture or in cell lysate, MDA combines with thiobarbituric acid (TBA) to form a fluorescent adduct that can be detected at an excitation wavelength of 530 nm and an emission wavelength of 550 nm. The results are then expressed as MDA equivalents, normalized to total cellular protein (determined by Bradford assay).

  13. Electrodiffusion of Lipids on Membrane Surfaces

    OpenAIRE

    Zhou, Y. C.

    2011-01-01

    Random lateral translocation of lipids and proteins is a universal process on membrane surfaces. Local aggregation or organization of lipids and proteins can be induced when this lateral random diffusion is mediated by the electrostatic interactions and membrane curvature. Though the lateral diffusion rates of lipids on membrane of various compositions are measured and the electrostatic free energies of predetermined protein-membrane-lipid systems can be computed, the process of the aggregati...

  14. Effect of tetrahydrocurcumin on lipid peroxidation and lipids in streptozotocin-nicotinamide-induced diabetic rats.

    Science.gov (United States)

    Murugan, Pidaran; Pari, Leelavinothan

    2006-08-01

    Hyperlipidaemia is an associated complication of diabetes mellitus. We recently reported that tetrahydrocurcumin lowered the blood glucose in diabetic rats. In the present study, we have investigated the effect of tetrahydrocurcumin, one of the active metabolites of curcumin on lipid profile and lipid peroxidation in streptozotocin-nicotinamide-induced diabetic rats. Tetrahydrocurcumin 80 mg/kg body weight was administered orally to diabetic rats for 45 days, resulted a significant reduction in blood glucose and significant increase in plasma insulin in diabetic rats, which proved its antidiabetic effect. Tetrahydrocurcumin also caused a significant reduction in lipid peroxidation (thiobarbituric acid reactive substances and hydroperoxides) and lipids (cholesterol, triglycerides, free fatty acids and phospholipids) in serum and tissues, suggesting its role in protection against lipid peroxidation and its antihyperlipidemic effect. Tetrahydrocurcumin showed a better effect when compared with curcumin. Results of the present study indicate that tetrahydrocurcumin showed antihyperlipidaemic effect in addition to its antidiabetic effect in type 2 diabetic rats.

  15. Study on mechanism of decreased lipid peroxide by low dose radiation

    International Nuclear Information System (INIS)

    Yamaoka, Kiyonori; Okazoe, Yoko; Akimaru, Kunihiro; Sato, E.F.; Utsumi, Kozo.

    1991-01-01

    We examined the effect of SOD on lipid peroxidation in biomembrane from V.E-deficient rats, in order to study the mechanism of increased SOD activities and decreased lipid peroxide by low dose irradiation. The following results were obtained. i. Active oxygen (O 2 - ) strongly enhances lipid peroxidations in biomembrane with the Fe 3+ as catalyst. ii. SOD evidently inhibits lipid peroxidations under above conditions. iii. We suggested that the effect of SOD enhanced by low dose irradiation results in inhibition of lipid peroxidation. (author)

  16. Potential for free radical-induced lipid peroxidation as a cause of endothelial cell injury in Rocky Mountain spotted fever.

    Science.gov (United States)

    Silverman, D J; Santucci, L A

    1988-01-01

    Cells infected by Rickettsia rickettsii, the causative agent of Rocky Mountain spotted fever, display unusual intracellular morphological changes characterized by dilatation of the membranes of the endoplasmic reticulum and outer nuclear envelope. These changes are consistent with those that might be expected to occur following peroxidation of membrane lipids initiated by oxygen radical species, such as the hydroxyl radical or a variety of organic radicals. Using a fluorescent probe, we have found significantly increased levels of peroxides in human endothelial cells infected by R. rickettsii. Studies with desferrioxamine, an iron chelator effective in preventing formation of the hydroxyl radical from hydrogen peroxide and the superoxide free radical, reduced peroxide levels in infected cells to those found in uninfected cells. This observation suggests that the increased peroxides in infected cells may be lipid peroxides, degradation products of free radical attack on polyenoic fatty acids. The potential for lipid peroxidation as an important mechanism in endothelial cell injury caused by R. rickettsii is discussed. Images PMID:3141280

  17. Role of lipid peroxidation in pathogenesis of senile cataract

    Directory of Open Access Journals (Sweden)

    Kisić Bojana

    2009-01-01

    Full Text Available Background /Aim. Cataract is a structural, biochemical and optical change in the eye lens, which changes transmission and refraction of light rays reducing keenness and clarity of a figure on the retina. Its occurrence is highest in older people, over the age of 65 (45.9%, thus a certain degree of opacification exists practically in all people over the 70. Our research was directed to measuring of lipid peroxidation products in cataract lenses involved in early stages of cataractogenesis through oxidative stress and in the development of mature cataract. Methods. Clinical and biochemical research was carried out in 101 patients with cataract, 46 women and 55 men. The average age of the group was 72.47 (ґ = 7.98. According to the cataract maturity degree the patients were classified into two groups as follows: cataracta senilis incipiens (n = 41 and cataracta senilis matura (n = 60. Measuring of diene conjugates was carried out by spectrophotometer. Fluorescent lipid peroxidation products were measured by a spectrofluorophotometer, and malondialdehyde (MDA concentration was measured by colorimeter as a product of a reaction with thiobarbituric acid (TBA. Result. Significantly higher diene conjugated concentration in lenses was measured in the patients with the diagnosis cataracta senilis incipiens (p < 0.001 as well as the intensity of fluorescent iminopropens (p < 0.001. Significantly higher MDA concentration in lens (p < 0.001 was measured in the patients with cataracta senilis matura. Conclusion. The lens structure changes caused by lipid peroxidation can, with other risk factors present, influence the occurrence and development of mature cataract. Some cataract types show different lipid peroxidation intensity with the most distinct changes in cataract which started as corticonuclear.

  18. Effect of exercise on lipid peroxidation in student soccer players

    OpenAIRE

    Puspaningtyas, Desty Ervira; Afriani, Yuni; Mahfida, Silvi Lailatul; Kushartanti, Wara; Farmawati, Arta

    2018-01-01

    Training is conducted to improve physiological functions that can support improvementof cardio-respiratory function (O2max). However, intensive training can lead to oxidativestress, which can contribute to health problems. The purpose of this study was to evaluatethe effect of training on serum lipid peroxidation levels in student soccer players. Thestudy was pre-experimental study with a one-shot case design conducted in April 2014.Twelve student soccer players from UGM who chosen by purposi...

  19. Glutathione delays varies as-tocopherol oxidation and subsequent lipid peroxidation in rat liver microsomes

    International Nuclear Information System (INIS)

    Robey, S.; Mavis, R.

    1986-01-01

    A method has been developed for in vitro trace radiolabeling of rat liver microsomes with 3 H-α-tocopherol (αT*) which allows virtually complete oxidation of the αT* under oxidizing conditions. The supernatant of a 16,000 xg centrifugation of homogenized rat liver, containing the cytosolic rat liver vitamin E (VE) transfer protein, was incubated with an ethanolic solution of αT* for 10 minutes at 37 0 C. Labeled microsomes were collected in the washed 100,000 xg pellet. Microsomes were then incubated with 30 μM Fe 2+ in an NADPH-generating system, and both production of malondialdehyde (MDA) (a product of lipid peroxidation) and oxidation of αT* were monitored over a time course in the presence and absence of glutathione (GSH). The results indicate virtually complete oxidation of αT* precedes significant membrane lipid peroxidation, and that addition of 5 mM GSH delays both αT* oxidation and subsequent MDA production. This suggests that the previously observed VE-dependent heat labile inhibition of microsomal lipid peroxidation by GSH involves maintaining membrane levels of α-tocopherol

  20. Levels of oxidative damage and lipid peroxidation in thyroid neoplasia.

    LENUS (Irish Health Repository)

    Young, Orla

    2012-02-01

    BACKGROUND: This study assessed the presence of oxidative damage and lipid peroxidation in thyroid neoplasia. METHODS: Using tissue microarrays and immunohistochemistry, we assessed levels of DNA damage (8-oxo-dG) and lipid peroxidation (4-HNE) in 71 follicular thyroid adenoma (FTA), 45 papillary thyroid carcinoma (PTC), and 17 follicular thyroid carcinoma (FTC) and matched normal thyroid tissue. RESULTS: Cytoplasmic 8-oxo-dG and 4-HNE expression was significantly higher in FTA, FTC, and PTC tissue compared to matched normal tissue (all p values < .001). Similarly, elevated nuclear levels of 8-oxo-dG were seen in all in FTA, FTC, and PTC tissue compared to matched normal (p values < .07, < .001, < .001, respectively). In contrast, a higher level of 4-HNE expression was detected in normal thyroid tissue compared with matched tumor tissue (p < .001 for all groups). Comparing all 3 groups, 4-HNE levels were higher than 8-oxo-dG levels (p < .001 for all groups) except that cytoplasmic levels of 8-oxo-dG were higher than 4-HNE in all (p < .001). These results were independent of proliferation status. CONCLUSION: High levels of DNA damage and lipid peroxidation in benign and malignant thyroid neoplasia indicates this damage is an early event that may influence disease progression.

  1. Modulatory effect of Scoparia dulcis in oxidative stress-induced lipid peroxidation in streptozotocin diabetic rats.

    Science.gov (United States)

    Latha, M; Pari, L

    2003-01-01

    In light of evidence that diabetes mellitus is associated with oxidative stress and altered antioxidant status, we investigated the effect of Scoparia dulcis plant extracts (SPEt) (aqueous, ethanolic, and chloroform) in streptozotocin diabetic rats. Significant increases in the activities of insulin, superoxide dismutase, catalase, glutathione peroxidase, glutathione-S-transferase, reduced glutathione, vitamin C, and vitamin E were observed in liver, kidney, and brain on treatment with SPEt. In addition, the treated groups also showed significant decreases in blood glucose, thiobarbituric acid-reactive substances, and hydroperoxide formation in tissues, suggesting its role in protection against lipid peroxidation-induced membrane damage. Thus, the results of the present study indicate that extracts of S. dulcis, especially the aqueous extract, showed a modulatory effect by attenuating the above lipid peroxidation in streptozotocin diabetes.

  2. Lipid peroxidation and water penetration in lipid bilayers

    DEFF Research Database (Denmark)

    Conte, Elena; Megli, Francesco Maria; Khandelia, Himanshu

    2012-01-01

    to the hydroperoxide groups to interact with the nitroxide at the methyl-terminal, confirming that the H-bonds experimentally observed are due to increased water penetration in the bilayer. The EPR and MD data on model membranes demonstrate that cell membrane damage by oxidative stress cause alteration of water......(zz) parameters revealed that OHPLPC, but mostly HpPLPC, induced a measurable increase in polarity and H-bonding propensity in the central region of the bilayer. Molecular dynamics simulation performed on 16-DSA in the PLPC-HpPLPC bilayer revealed that water molecules are statistically favored with respect...

  3. Studies on the lipid peroxidation in mitochondria of x-ray whole-body irradiated rat liver, 2

    International Nuclear Information System (INIS)

    Wakabayashi, Hiroshi

    1976-01-01

    The results of investigation made on the mitochondria of rat liver on the 3rd day after irradiation of 650 R are as follows: After lipid peroxidation, the mitochondria showed a decrease of polyenoic acids (C-20:4, C-22:6) suggesting that polyenoic acids are the substrate of the reaction. Unsaturated fatty acids were decreased due to the decrement of C-18:1 and C-18:2, and polyenoic acid was relatively increased. These changes were transient, reaching a maximum on the 3rd day after irradiation. The rate of peroxidation in total lipids extracted form normal mitochondria was the same as that from whole-body irradiated mitochondria. There was no lag in the induction period in either reaction. Marked peroxidation of the total lipid was seen in the phospholipid fraction and slight peroxidation in the simple lipid fractions. No significant effect of whole-body irradiation on the peroxidation activities of the phospholipid was observed. With thin-layer chromatography, peroxidation of subfractionated phospholipid showed marked activity in the lecithin and aminophosphatide fractions containing large amounts of C-20:4 and C-22.6. Recovery of activity in the subfractions was greater than that in the total phospholipid. The effect of whole-body irradiation appeared to be significant in these subfractions. However no relationships could be seen between the activities peroxidation and the fatty acid composition of the subfractions. The ratio of phospholipid to total lipid increased in whole-body irradiated samples. From these findings there was a discussion of whether or not Fe ++ -induced lipid peroxidation at the mitochondrial level is due to change in the composition of fatty acid and the association of lipid in the membrane. (Evans, J.)

  4. Effect of cadmium exposure on lipids, lipid peroxidation and metal distribution in rat brain regions

    Energy Technology Data Exchange (ETDEWEB)

    Hussain, T; Ali, M M; Chandra, S V

    1985-01-01

    Effect of cadmium treatment on brain lipids, lipid peroxidation and distribution of Zn, Cu and Fe in rat brain regions was investigated. Adult male rats were exposed to Cd (100 ppm Cd as cadmium acetate) in drinking water for 30 days. The Cd exposure resulted in a significant decrease in the phospholipid content and an increase in the lipid peroxidation in the cerebral cortex and cerebellum. The total lipid content was not affected in any of the regions but a significant decrease in cholesterol and cerebroside contents were observed only in the cerebral cortex. A positive correlation between the increase in lipid peroxidation and decrease in the phospholipid content in the cerebral cortex and cerebellum was observed. A maximum accumulation of Cd occurred in the cerebral cortex. The Cu and Fe contents were significantly increased but the Zn levels decreased in the Cd-treated rats in all but the midbrain region. Results suggest that the increased peroxidation decomposition of structural lipids and the altered distribution of the essential trace metals in brain may play a significant role in Cd-induced neurotoxicity. 27 references, 2 tables.

  5. Atomistic Monte Carlo simulation of lipid membranes

    DEFF Research Database (Denmark)

    Wüstner, Daniel; Sklenar, Heinz

    2014-01-01

    Biological membranes are complex assemblies of many different molecules of which analysis demands a variety of experimental and computational approaches. In this article, we explain challenges and advantages of atomistic Monte Carlo (MC) simulation of lipid membranes. We provide an introduction...... of local-move MC methods in combination with molecular dynamics simulations, for example, for studying multi-component lipid membranes containing cholesterol....

  6. Phototransformation of membrane lipids and its role in biomembrane function change under the effect of UV-radiation

    International Nuclear Information System (INIS)

    Roshchupkin, D.I.; Anosov, A.K.; Murina, M.A.; Lordkipanidze, A.T.

    1988-01-01

    The papers devoted to the investigation of photochemical transformations of lipid under the effect of UV radiation of biological membranes are reviewed. The mechanism of peroxide photooxidation of mebrane lipid is considered. Data on the effect of antioxidants and the structure state of membranes on the process of peroxide photooxidation of lipid are presented. The problem on the role of this process under the effect of UV-radiation on blood and skin of mammals is discussed. 48 refs.; 4 refs

  7. Lipids as organizers of cell membranes.

    Science.gov (United States)

    Kornmann, Benoît; Roux, Aurélien

    2012-08-01

    The 105th Boehringer Ingelheim Fonds International Titisee Conference 'Lipids as Organizers of Cell Membranes' took place in March 2012, in Germany. Kai Simons and Gisou Van der Goot gathered cell biologists and biophysicists to discuss the interplay between lipids and proteins in biological membranes, with an emphasis on how technological advances could help fill the gap in our understanding of the lipid part of the membrane.

  8. Lycopene control of benzophenone-sensitized lipid peroxidation

    Science.gov (United States)

    Cvetković, Dragan; Marković, Dejan

    2012-05-01

    Lycopene antioxidant activity in the presence of two different mixtures of phospholipids in hexane solution, under continuous regime of UV-irradiation from three different ranges (UV-A, UV-B, and UV-C) has been evaluated in this work. Lycopene expected role was to control lipid peroxidation, by scavenging free radicals generated by UV-irradiation, in the presence and in the absence of selected photosensitizer, benzophenone. This work shows that lycopene undergoes to UV-induced destruction (bleaching), highly dependent on the incident photons energy input, more expressed in the presence than in the absence of benzophenone. The further increase ("excess") of its bleaching is undoubtedly related to the further increase of its antioxidant activity in the presence of benzophenone, having the same cause: increase of (phospholipids peroxidation) chain-breaking activities.

  9. Lipid peroxidation is increased in tears from the elderly.

    Science.gov (United States)

    Benlloch-Navarro, Soledad; Franco, Ilenia; Sánchez-Vallejo, Violeta; Silvestre, Dolores; Romero, Francisco Javier; Miranda, María

    2013-10-01

    We describe a procedure in which tears, obtained from Schirmer strips, are used to measure a marker of lipid peroxidation, malondialdehyde (MDA). We also compared the levels of proteins and MDA in tears from two groups of people: young adults (18-30 years old) and elderly adults (65-85 years old), because the data related to total protein concentration of human tears vary widely and because the majority of people over the age of 65 experience some symptoms of dry eyes and this condition has been recognized as an oxidative stress-induced disease. Our results show a significant difference in the protein concentration of the tears taken from the two age categories, younger adults (18-30 years old) and older adults (65-85 years old). Herein, we report for the first time an increase in MDA concentrations determined by HPLC in human tears based on age. It is possible that alterations in the tear lipid layer may lead to an increase in lipid peroxidation. Further studies are needed to understand the nature and function of tear film and stability in order to obtain new methods to analyze tears in patients with different diseases. In this sense, it would be interesting to compare MDA concentration in tears from control subjects and from people with meibomian gland dysfunction. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Studies on lipid peroxidation and anti-LPO chemicals

    International Nuclear Information System (INIS)

    Wang Chongdao; Qiang Yizhong; Lao Qinhua

    1995-02-01

    The contents of lipid peroxides (LPO) in sera and tissues were determined by the modified spectrophotometry of TBA, and the effects of three chemicals on lipid peroxidation induced by radiation were observed. The items studied included: (1) the normal values of LPO of sera in rats and adults: (2) the normal values in some tissues of rats; (3) the changes of LPO levels of sera in patients with some mental diseases and patients with malignant tumours before and after local gamma irradiation exposure; (4) the changes of LPO contents of some tissues in rats after whole-body gamma irradiation exposure; (5) the changes of LPO contents of some tissues in mice after internal exposure by Th(NO 3 ) 4 solution; (6) the effects of chinonin, tannic acid and squalene on lipid peroxidation induced by irradiation. The results were as follows: (1) the LPO contents in patients with some mental diseases dramatically increased; (2) there was marked difference between the LPO levels before and after local gamma irradiation exposure in patients with malignant tumours; (3) the LPO contents in some tissues of rats remarkably increased after whole-body gamma irradiation exposure; (4) the LPO contents in some tissues of mice dramatically increased and their protein contents markedly reduced after internal exposure, showing a negative correlation between them; (5) a gradual increase in LPO contents in some tissues of mice appeared with increasing dosage of whole-body gamma irradiation exposure at dose range from 0 to 4 Gy. A linear relationship between the dose and the LPO contents was observed; (6) all three chemicals could reduce the LPO levels in liver, spleen and kidney of the irradiated mice. The efficacy of chinonin was better than that of tannic acid and squalene. (5 tabs., 1 fig.)

  11. Inhibition of Lipid Peroxidation by Enzymatic Hydrolysates from Wheat Bran

    Directory of Open Access Journals (Sweden)

    Yanping Cao

    2011-01-01

    Full Text Available Wheat bran, an important by-product of the cereal industry, is rich in potentially health-promoting phenolic compounds. The phenolics are mainly esterified to the cell wall polysaccharides. In our previous paper, wheat bran was destarched and deproteinated by α-amylase, protease and amyloglucosidase successively and further hydrolyzed using Bacillus subtilis xylanases, and the enzymatic hydrolysates from wheat bran (EHWB showed good scavenging activity in vitro. The aim of this study is to further characterize the antioxidant potential of EHWB against various systems, both ex vivo and in vivo, namely, rat liver microsomal lipid peroxidation systems induced by Fe2+/H2O2 and Fe3+-adenosine diphosphate (ADP/dihydronicotinamide adenine dinucleotide phosphate (NADPH, copper- and 2,2’-azo-bis(2-amidinopropane dihydrochloride (AAPH-induced human low-density lipoprotein (LDL oxidation systems, and alloxan-induced in vivo lipid peroxidation in mice. EHWB inhibited lipid peroxidation in rat liver microsomes induced by Fe2+/H2O2 and Fe3+-ADP/NADPH in a concentration-dependent manner with 90.3 and 87 % inhibition of lipid peroxidation at 50 mg/L, respectively, which were similar to that of butylated hydroxytoluene (BHT at 20 mg/L. The antioxidant potential of EHWB at a concentration ranging from 10 to 20 mg/L in the nonenzymatic system was more effective than in the enzymatic system. EHWB strongly inhibited in vitro copper- and AAPH-mediated oxidation of LDL in a concentration- and time-dependent manner with 52.41 and 63.03 % inhibition at 20 mg/L, respectively, which were similar to that of ascorbate at 10 mg/L. EHWB significantly decreased the level of thiobarbituric acid reactive substances (TBARS and increased the activities of glutathione peroxidase (GSH-Px, catalase (CAT and superoxide dismutase (SOD in serum and liver of alloxan-treated mice compared with the control. These results demonstrated that EHWB might be efficient in the protection of

  12. Lipid peroxidation, occupational stress and aging in workers of a prehospital emergency service.

    Science.gov (United States)

    Casado, Angela; De Lucas, Nieves; López-Fernández, Encarnación; Sánchez, Alberto; Jimenez, José-Antonio

    2006-06-01

    Stressful conditions lead to formation of excessive free radicals, and lipid peroxidation is one of the major outcomes of free radical-mediated injury that directly damages membranes and generates a number of secondary products. To determine the levels of malondialdehyde, an end product of lipid peroxidation, according to demographic and occupational variables in workers of a prehospital emergency service and to analyse the relationship between malondialdehyde levels and burnout. One hundred and eleven healthy workers of a prehospital emergency service and eighty aged-matched healthy individuals of both sexes as a control group were surveyed. Malondialdehyde levels were measured by the Bull and Marnett method. To measure burnout, the Maslach Burnout Inventory was used. Professional category is associated with lipid peroxidation and burnout levels (Malondialdehyde levels were: physicians 338.10+/-14.47, nurses 329.17+/-12.62 and technicians 296.74+/-14.28; burnout levels were: physicians 41.29+/-3.59, nurses 37.38+/-6.05 and technicians 35.33+/-5.87). Working at night and in the evening increased malondialdehyde and burnout levels. Malondialdehyde levels increase with age. No significant variations with respect to sex were detected. Significant variations in malondialdehyde levels were detected between singles (303.13+/-12.74) and married people (344.43+/-13.43) but not with respect to divorcees (326.44+/-11.74). Significant differences were detected in erythrocyte malondialdehyde levels between smokers (341.37+/-17.09) and nonsmokers (302.21+/-12.38), but not for alcohol consumption. These findings suggest a positive correlation between malondialdehyde, a biomarker of lipid peroxidation and occupational stress, as estimated by elements of the Maslach Burnout Inventory, and oxidative stress.

  13. Electrodiffusion of lipids on membrane surfaces.

    Science.gov (United States)

    Zhou, Y C

    2012-05-28

    Lateral translocation of lipids and proteins is a universal process on membrane surfaces. Local aggregation or organization of lipids and proteins can be induced when the random lateral motion is mediated by the electrostatic interactions and membrane curvature. Although the lateral diffusion rates of lipids on membranes of various compositions are measured and the electrostatic free energies of predetermined protein-membrane-lipid systems can be computed, the process of the aggregation and the evolution to the electrostatically favorable states remain largely undetermined. Here we propose an electrodiffusion model, based on the variational principle of the free energy functional, for the self-consistent lateral drift-diffusion of multiple species of charged lipids on membrane surfaces. Finite sizes of lipids are modeled to enforce the geometrical constraint of the lipid concentration on membrane surfaces. A surface finite element method is developed to appropriate the Laplace-Beltrami operators in the partial differential equations of the model. Our model properly describes the saturation of lipids on membrane surfaces, and correctly predicts that the MARCKS peptide can consistently sequester three multivalent phosphatidylinositol 4,5-bisphosphate lipids through its basic amino acid residues, regardless of a wide range of the percentage of monovalent phosphatidylserine in the membrane.

  14. [Germ cell membrane lipids in spermatogenesis].

    Science.gov (United States)

    Wang, Ting; Shi, Xiao; Quan, Song

    2016-05-01

    Spermatogenesis is a complex developmental process in which a diploid progenitor germ cell transforms into highly specialized spermatozoa. During spermatogenesis, membrane remodeling takes place, and cell membrane permeability and liquidity undergo phase-specific changes, which are all associated with the alteration of membrane lipids. Lipids are important components of the germ cell membrane, whose volume and ratio fluctuate in different phases of spermatogenesis. Abnormal lipid metabolism can cause spermatogenic dysfunction and consequently male infertility. Germ cell membrane lipids are mainly composed of cholesterol, phospholipids and glycolipids, which play critical roles in cell adhesion and signal transduction during spermatogenesis. An insight into the correlation of membrane lipids with spermatogenesis helps us to better understand the mechanisms of spermatogenesis and provide new approaches to the diagnosis and treatment of male infertility.

  15. Lipid peroxidation in workers exposed to hexavalent chromium.

    Science.gov (United States)

    Huang, Y L; Chen, C Y; Sheu, J Y; Chuang, I C; Pan, J H; Lin, T H

    1999-02-26

    The aim of this study was to investigate whether exposure to hexavalent chromium induces lipid peroxidation in human. This study involved 25 chrome-plating factory workers and a reference group of 28 control subjects. The whole-blood and urinary chromium concentrations were determined by graphite furnace atomic absorption spectrophotometry. Malondialdehyde (MDA), the product of lipid peroxidation, was determined by high-performance liquid chromatography, and the activities of protective enzymes were measured by ultraviolet-visible spectrophotometry. In the chrome-plating workers, the mean concentrations of chromium in blood and urine were 5.98 microg/L and 5.25 microg/g creatinine, respectively; the mean concentrations of MDA in blood and urine were 1.7 micromol/L and 2.24 micromol/g creatinine. The concentrations of both chromium and MDA in blood and urine were significantly higher in the chromium-exposed workers. The activities of superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT) were not markedly different between control and exposed workers. Data suggest that MDA may be used as a biomarker for occupational chromium exposure. Antioxidant enzymic activities are not a suitable marker for chromium exposure.

  16. Ionizing radiation and lipid peroxidation in human body; Radiazioni ionizzanti e perossidazione lipidica nell`organismo umano

    Energy Technology Data Exchange (ETDEWEB)

    Giubileo, Gianfranco [ENEA, Centro Ricerche Frascati, Roma (Italy)

    1997-07-01

    Lipids are organic compounds constituting the living cells. Lipid molecules can be disassembled through peroxidative pathways and hydrocarbons can be bred as end-product of lipid peroxidation in vivo. Lipid peroxidation can be started by an indirect effect of ionizing radiation. So a radioinduced cellular damage in human body can be detected by monitoring the production of specific hydrocarbons.

  17. Pollen viability and membrane lipid composition

    NARCIS (Netherlands)

    Bilsen, van D.G.J.L.

    1993-01-01

    In this thesis membrane lipid composition is studied in relation to pollen viability during storage. Chapter 1 reviews pollen viability, membranes in the dry state and membrane changes associated with cellular aging. This chapter is followed by a study of age-related changes in phospholipid

  18. Lipid organization of the plasma membrane

    NARCIS (Netherlands)

    Ingólfsson, Helgi I; Melo, Manuel N; van Eerden, Floris J; Arnarez, Clément; Lopez, Cesar A; Wassenaar, Tsjerk A; Periole, Xavier; de Vries, Alex H; Tieleman, D Peter; Marrink, Siewert J

    2014-01-01

    The detailed organization of cellular membranes remains rather elusive. Based on large-scale molecular dynamics simulations, we provide a high-resolution view of the lipid organization of a plasma membrane at an unprecedented level of complexity. Our plasma membrane model consists of 63 different

  19. Artificial Lipid Membranes: Past, Present, and Future.

    Science.gov (United States)

    Siontorou, Christina G; Nikoleli, Georgia-Paraskevi; Nikolelis, Dimitrios P; Karapetis, Stefanos K

    2017-07-26

    The multifaceted role of biological membranes prompted early the development of artificial lipid-based models with a primary view of reconstituting the natural functions in vitro so as to study and exploit chemoreception for sensor engineering. Over the years, a fair amount of knowledge on the artificial lipid membranes, as both, suspended or supported lipid films and liposomes, has been disseminated and has helped to diversify and expand initial scopes. Artificial lipid membranes can be constructed by several methods, stabilized by various means, functionalized in a variety of ways, experimented upon intensively, and broadly utilized in sensor development, drug testing, drug discovery or as molecular tools and research probes for elucidating the mechanics and the mechanisms of biological membranes. This paper reviews the state-of-the-art, discusses the diversity of applications, and presents future perspectives. The newly-introduced field of artificial cells further broadens the applicability of artificial membranes in studying the evolution of life.

  20. Effects of Ferulago angulata Extract on Serum Lipids and Lipid Peroxidation

    Directory of Open Access Journals (Sweden)

    Mahmoud Rafieian-kopaei

    2014-01-01

    Full Text Available Background. Nowadays, herbs they are considered to be the main source of effective drugs for lowering serum lipids and lipid peroxidation. The present experimental animal study aimed to assess the impact of Ferulago angulata on serum lipid profiles, and on levels of lipid peroxidation. Methods. Fifty male Wistar rats, weighing 250–300 g, were randomly divided into five equal groups (ten rats in each. The rat groups received different diets as follows: Group I: fat-rich diet; Group II: fat-rich diet plus hydroalcoholic extracts of Ferulago angulata at a dose of 400 mg/kg; Group III: fat-rich diet plus hydroalcoholic extracts of Ferulago angulata at a dose of 600 mg/kg; Group IV: fat-rich diet plus atorvastatin; Group V: common stock diet. The levels of serum glucose and lipids and the atherogenic index were measured. In addition, malondialdehyde (MDA, thiol oxidation, carbonyl concentrations, C-reactive proteins, and antioxidant capacity were evaluated in each group of rats. Results. Interestingly, by adding a hydroalcoholic extract of Ferulago angulata to the high-fat diet, the levels of total cholesterol and low-density lipoproteins (LDL in the high-fat diet rats were both significantly reduced. This result was considerably greater compared to when atorvastatin was added as an antilipid drug. The beneficial effects of the Ferulago angulata extract on lowering the level of triglycerides was observed only when a high dosage of this plant extraction was added to a high fat diet. Furthermore, the level of malondialdehyde, was significantly affected by the use of the plant extract in a high-fat diet, compared with a normal regimen or high-fat diet alone. Conclusion. Administration of a hydroalcoholic extract of Ferulago angulata can reduce serum levels of total cholesterol, triglycerides, and LDL. It can also inhibit lipid peroxidation.

  1. Protective effect of morin on lipid peroxidation and lipid profile in ammonium chloride-induced hyperammonemic rats

    Directory of Open Access Journals (Sweden)

    S Subash

    2012-04-01

    Full Text Available Objective: To evaluated the protective effects of morin (3, 5, 7, 2', 4'-pentahydroxyflavone on lipid peroxidation and lipid levels during ammonium chloride (AC induced hyperammonemia in experimental rats. Methods: Thirty two male albino Wistar rats, which are weighing between 180-200 g were used for the study. The hyperammonemia was induced by administration of 100 mg/kg body weight (i.p. thrice in a week of AC for 8 weeks. Rats were treated with morin at dose (30 mg/kg body weight via intragastric intubations together with AC. At the end of experimental duration, blood ammonia, plasma urea, lipid peroxidation indices [thiobarbituric acid reactive substances, hydroperoxides and lipid levels (cholesterol, triglycerides, free fatty acids and phospholipids] in serum and tissues were analysed to evaluate the antiperoxidative and antilipidemic effects of morin. Results: Ammonia, urea, lipid peroxidative indices and lipid levels were significantly increased in AC administered group. Morin treatment resulted in positive modulation of ammonia, urea, lipid peroxidative indices and lipid levels. Morin administration to normal rats did not exhibit any significant changes in any of the parameters studied. Conclusions: It can be concluded that the beneficial effect of morin on ammonia, urea, lipid peroxidative indices and lipid levels could be due to its antioxidant property.

  2. The state of lipid peroxidation and the antioxidant system in victims of the Chernobyl accident that suffer from duodenal ulcer

    International Nuclear Information System (INIS)

    Kucherenko, M.Je.; Drobyins'ka, O.V.; Ostapchenko, L.Yi.

    2002-01-01

    In the bioptates of mucous membranes of stomach in peptic ulcer patients residing in the regions with a high level of contamination by radionuclides, a high level of products of lipid peroxidation is found. It is experimentally proved that the violations are accompanied by a significant fall of the level of antioxidant enzymes and warrant a wide use of direct antioxidant medicine to normalize all the above-mentioned processes

  3. Lipid peroxidation regulates podocyte migration and cytoskeletal structure through redox sensitive RhoA signaling

    Directory of Open Access Journals (Sweden)

    Claudia Kruger

    2018-06-01

    Full Text Available Early podocyte loss is characteristic of chronic kidney diseases (CKD in obesity and diabetes. Since treatments for hyperglycemia and hypertension do not prevent podocyte loss, there must be additional factors causing podocyte depletion. The role of oxidative stress has been implicated in CKD but it is not known how exactly free radicals affect podocyte physiology. To assess this relationship, we investigated the effects of lipid radicals on podocytes, as lipid peroxidation is a major form of oxidative stress in diabetes. We found that lipid radicals govern changes in podocyte homeostasis through redox sensitive RhoA signaling: lipid radicals inhibit migration and cause loss of F-actin fibers. These effects were prevented by mutating the redox sensitive cysteines of RhoA. We therefore suggest that in diseases associated with increased lipid peroxidation, lipid radicals can determine podocyte function with potentially pathogenic consequences for kidney physiology. Keywords: Lipid peroxidation, Reactive lipids, Podocyte, RhoA, Cysteine, Chronic kidney disease

  4. The effects of antioxidant vitamin supplementation on resistance exercise induced lipid peroxidation in trained and untrained participants

    Directory of Open Access Journals (Sweden)

    LaVoie Norm

    2004-06-01

    Full Text Available Abstract Background The theoretical benefits of using antioxidant vitamin supplements to quench oxygen free radicals appear large. High intensity aerobic-type exercise produces oxygen free radicals that can cause damage to lipid membranes (lipid peroxidation that may lead to many problems such as the inactivation of cell membrane enzymes, the progression of degenerative diseases (cardiovascular disease and cancer and lessening of the effectiveness of the immune system. The major function of vitamin E is to work as a chain-breaking antioxidant in a fat soluble environment. Little research has examined lipid peroxidation associated with high intensity resistance exercise or possible protective effects of antioxidant supplementation or the effects of training state. Results There were no significant group (trained vs untrained or treatment (vitamin E vs placebo effects found between the 4 groups assessed. There was only one significant difference found and that was in the main effect for time (F = 22.41, p Conclusions The Resistance Exercise Test caused a significant increase in malondialdehyde in all 4 groups at 6 hours post exercise. There was no evidence that vitamin E supplementation was effective in reducing oxidative damage in comparison to the placebo group. As well, there was no difference between the trained and untrained groups with respect to their impact on lipid peroxidation measures.

  5. Lipid peroxidation: A phytotoxic consequence of air pollutants

    Energy Technology Data Exchange (ETDEWEB)

    Kunert, K J; Mehlhorn, H; Schmidt, A; Horsch, F; Filby, G; Fund, N; Gross, S; Hanisch, B; Kilz, E; Seidel, A [comps.

    1986-04-01

    Spruce and fir, both 10 years of age, were exposed to purified air, ozone (0.14 mg/m/sup 3/ air), SO/sub 2/ (0.03 mg/m/sup 3/ air), or a combination of both gases in open top chambers. With age, a combination of both gases significantly increased the content of the antioxidants vitamin E and C and glutathione in needles of fir and spruce when compared to the control treated with purified air. The increase was stronger in needles of fir than in needles of spruce. Further, the increase was already found in the youngest needles of fir. Compared to the control, no significant higher amount of antioxidants was observed when trees were exposed to ozone alone. Moreover, ozone exposure was less effective than SO/sub 2/ exposure. Combination of both air pollutants induced synergistic effects. In field studies (location: Schwarzwald, Kaelbelescheuer/Haldenhof), needles of spruce also showed an increase in the vitamin E content dependent on the extent of damage. This increase was partly accompanied by a higher amount of vitamin C and an increased degree of lipid peroxidation, measured as ethane production. Our results from open top experiments are consistent with our previous data investigating natural aging in higher plants. Therefore we suggest that by the phytotoxic action of air pollutants, such as SO/sub 2/ and SO/sub 2/ + ozone, age-related peroxidative processes are accelerated. Further, both vitamin E and glutathione are specific indicators of these processes. By now, no direct and significant correlation between field studies and studies with open tops has been found.

  6. Five Decades with Polyunsaturated Fatty Acids: Chemical Synthesis, Enzymatic Formation, Lipid Peroxidation and Its Biological Effects

    Directory of Open Access Journals (Sweden)

    Angel Catalá

    2013-01-01

    Full Text Available I have been involved in research on polyunsaturated fatty acids since 1964 and this review is intended to cover some of the most important aspects of this work. Polyunsaturated fatty acids have followed me during my whole scientific career and I have published a number of studies concerned with different aspects of them such as chemical synthesis, enzymatic formation, metabolism, transport, physical, chemical, and catalytic properties of a reconstructed desaturase system in liposomes, lipid peroxidation, and their effects. The first project I became involved in was the organic synthesis of [1-14C] eicosa-11,14-dienoic acid, with the aim of demonstrating the participation of that compound as a possible intermediary in the biosynthesis of arachidonic acid “in vivo.” From 1966 to 1982, I was involved in several projects that study the metabolism of polyunsaturated fatty acids. In the eighties, we studied fatty acid binding protein. From 1990 up to now, our laboratory has been interested in the lipid peroxidation of biological membranes from various tissues and different species as well as liposomes prepared with phospholipids rich in PUFAs. We tested the effect of many antioxidants such as alpha tocopherol, vitamin A, melatonin and its structural analogues, and conjugated linoleic acid, among others.

  7. Assessing the nature of lipid raft membranes

    DEFF Research Database (Denmark)

    Niemelä, Perttu S; Ollila, Samuli; Hyvönen, Marja T

    2007-01-01

    of highly ordered lateral domains rich in sphingomyelin and cholesterol (CHOL). These domains, called functional lipid rafts, have been suggested to take part in a variety of dynamic cellular processes such as membrane trafficking, signal transduction, and regulation of the activity of membrane proteins......-scale simulations to elucidate the properties of ternary raft mixtures with CHOL, palmitoylsphingomyelin (PSM), and palmitoyloleoylphosphatidylcholine. We simulate two bilayers of 1,024 lipids for 100 ns in the liquid-ordered phase and one system of the same size in the liquid-disordered phase. The studies provide...... heterogeneity more difficult. The findings reveal aspects of the role of favored (specific) lipid-lipid interactions within rafts and clarify the prominent role of CHOL in altering the properties of the membrane locally in its neighborhood. Also, we show that the presence of PSM and CHOL in rafts leads...

  8. Binding of Neurotransmitters to Lipid Membranes

    DEFF Research Database (Denmark)

    Peters, Günther H.J.; Werge, Mikkel; Elf-Lind, Maria Northved

    2014-01-01

    / acetylated g-aminobutyrate (GABAneu) with a dipalmitoylphosphatidylcholine (DPPC) bilayer. This study was motivated by recent research results that suggested that neural transmission may also be affected by nonspecific interactions of NTs with the lipid matrix of the synaptic membrane. Our results revealed...... backbone of the phospholipids. It is surprising that hydrophilic solutes can deeply penetrate into the membrane pointing to the fact that membrane affinity is governed by specific interactions. Our MD simulations identified the salt-bridge between the primary amine of NTs and the lipid phosphate group...

  9. Radioprotective effect of Panax ginseng on the phosphatases and lipid peroxidation level in testes of Swiss albino mice

    Energy Technology Data Exchange (ETDEWEB)

    Kumar M.; Sharma M.K.; Saxena P.S.; Kumar A. [Rajasthan Univ., Jaipur (India)

    2003-03-01

    The Panax ginseng has been used as traditional medicine for past several years among oriental people. The present investigation has been made to assess the radioprotective efficacy of ginseng root extract in the testicular enzymes of Swiss albino mice. The Swiss albino mice were divided into different groups. Ginseng treated group: The animals were administered 10 mg/kg body weight ginseng root extract intraperitoneal (i.p.). Radiation treated group: The animals were exposed to 8 Gy gamma radiation at the dose rate of 1.69 Gy/min at the distance of 80 cm. Combination group: Animals were administered ginseng extract continuously for 4 d and on 4th day they were irradiated to 8 Gy gamma radiation after 30 min of extract administration. The animals from above groups were autopsied on day 1, 3, 7, 14 and 30. Biochemical estimations of acid and alkaline phosphatases and Lipid peroxidation (LPO) in testes were done. In ginseng treated group acid and alkaline phosphatases activity and LPO level did not show any significant alteration. In irradiated animals there was a significant increase in acid phosphatase activity and LPO level. However, significant decline in alkaline phosphatase activity was observed. The treatment of ginseng before irradiation causes significant decrease in acid phosphatase and LPO level and significant increase in alkaline phosphatase activity. One of the cause of radiation damage is lipid peroxidation. Due to lipid peroxidation, lysosomal membrane permeability alters and thus results in release of hydrolytic enzymes. So, an increase in acid phosphatase was noticed after radiation treatment. The alkaline phosphatase activity is associated with membrane permeability and different stages of spermatogenesis. Due to membrane damage and depletion of germ cells of testes after irradiation the enzyme activity was decreased. Ginseng markedly inhibits lipid peroxidation. It acts in indirect fashion to protect radical processes by inhibition of initiation of

  10. Radioprotective effect of Panax ginseng on the phosphatases and lipid peroxidation level in testes of Swiss albino mice

    International Nuclear Information System (INIS)

    Kumar, M.; Sharma, M.K.; Saxena, P.S.; Kumar, A.

    2003-01-01

    The Panax ginseng has been used as traditional medicine for past several years among oriental people. The present investigation has been made to assess the radioprotective efficacy of ginseng root extract in the testicular enzymes of Swiss albino mice. The Swiss albino mice were divided into different groups. Ginseng treated group: The animals were administered 10 mg/kg body weight ginseng root extract intraperitoneal (i.p.). Radiation treated group: The animals were exposed to 8 Gy gamma radiation at the dose rate of 1.69 Gy/min at the distance of 80 cm. Combination group: Animals were administered ginseng extract continuously for 4 d and on 4th day they were irradiated to 8 Gy gamma radiation after 30 min of extract administration. The animals from above groups were autopsied on day 1, 3, 7, 14 and 30. Biochemical estimations of acid and alkaline phosphatases and Lipid peroxidation (LPO) in testes were done. In ginseng treated group acid and alkaline phosphatases activity and LPO level did not show any significant alteration. In irradiated animals there was a significant increase in acid phosphatase activity and LPO level. However, significant decline in alkaline phosphatase activity was observed. The treatment of ginseng before irradiation causes significant decrease in acid phosphatase and LPO level and significant increase in alkaline phosphatase activity. One of the cause of radiation damage is lipid peroxidation. Due to lipid peroxidation, lysosomal membrane permeability alters and thus results in release of hydrolytic enzymes. So, an increase in acid phosphatase was noticed after radiation treatment. The alkaline phosphatase activity is associated with membrane permeability and different stages of spermatogenesis. Due to membrane damage and depletion of germ cells of testes after irradiation the enzyme activity was decreased. Ginseng markedly inhibits lipid peroxidation. It acts in indirect fashion to protect radical processes by inhibition of initiation of

  11. Importance of the lipid peroxidation biomarkers and methodological aspects FOR malondialdehyde quantification

    Directory of Open Access Journals (Sweden)

    Denise Grotto

    2009-01-01

    Full Text Available Free radicals induce lipid peroxidation, playing an important role in pathological processes. The injury mediated by free radicals can be measured by conjugated dienes, malondialdehyde, 4-hydroxynonenal, and others. However, malondialdehyde has been pointed out as the main product to evaluate lipid peroxidation. Most assays determine malondialdehyde by its reaction with thiobarbituric acid, which can be measured by indirect (spectrometry and direct methodologies (chromatography. Though there is some controversy among the methodologies, the selective HPLC-based assays provide a more reliable lipid peroxidation measure. This review describes significant aspects about MDA determination, its importance in pathologies and biological samples treatment.

  12. Lipid Peroxidation and Electrolytes in Irradiated Rats Treated with Caffeine

    International Nuclear Information System (INIS)

    Abdel-Gawad, I.I.; Ahmed, A.M.

    2005-01-01

    This Study was conducted to elarify the potential role of caffeine (1,3,7-trimethyl xanthine), a major component of coffee, against damages induced by gamma rays. Thirty adult female albino rats (130+10) were divided into three groups, each of ten animals. The first group acted as control animals. The second was sujected to a single dose of (7) Gy whole body gamma irradiation. The third group was injected intraperitoneally with a single dose (80mg/kg body weight) of caffeine one-hour prior irradiation. Blood samples were collected five time intervals 1,3,7,15 and 30 days post-irradiation. The content of serum lipid peroxides was measured as thiobarbituric acid reactive substance (TBARS). Electrolytes as calcium (Ca2 + ), sodium (Na + ) and potassium (K + ) and levels were estimated and Na + /K + ratio was calculated. Also serum enzymes as alkaline phosphatase (ALP) and aminotransaminases (AST and ALT) activity levels were measured. The data revealed significant increase in TBARS, AST and ALT levels in serum due to irradiation exposure. While, radiation induced significant decrease in serum level of ALP, level of electrolytes Ca 2+ , Ma + , and Na + /K + ratio. On the other hand, group injected intraperitoneally with caffeine pre-irradiation exhibited reduction in the changes produced by gamma-radiation with variable degree. The data showed that this antioxidant confers protection damage inflicted by radiation when given prior to irradiation exposure on the examined parameters

  13. Lipid Peroxidation in Rat Liver using Different Vegetable Oils

    International Nuclear Information System (INIS)

    Eqbal Dauqan; Aminah Abdullah; Halimah Abdullah Sani

    2013-01-01

    The objective of the study was to evaluate the effect of different vegetable oils (Red Palm Olien (RPO), Palm Olein (PO), Corn Oil (CO) and Coconut Oil on lipid peroxidation of rat liver. One hundred and thirty two Sprague Dawley male rats were randomly divided into two groups. The first group contains seventy two rats were divided into twelve groups of 6 rats per group and were treated with different concentrations of RPO (5 %, 10 % and 15 %) for 2, 4 and 8 weeks. The second group contains sixty male rats were randomly divided into ten groups of 6 rats per group and were treated with 15 % of RPO, PO, CO and COC for 4 and 8 weeks. The results shows that after 8 weeks of treatment the malonaldehyde (MDA) value in RPO group was significantly lower (P≤0.05) than control or vegetable oils studied. These experiments suggested that red palm olein antioxidants present in rat diets may better attenuate peroxyl radical than other vegetable oil studied. (author)

  14. Biosynthesis of archaeal membrane ether lipids

    Directory of Open Access Journals (Sweden)

    Samta eJain

    2014-11-01

    Full Text Available A vital function of the cell membrane in all living organism is to maintain the membrane permeability barrier and fluidity. The composition of the phospholipid bilayer is distinct in archaea when compared to bacteria and eukarya. In archaea, isoprenoid hydrocarbon side chains are linked via an ether bond to the sn-glycerol-1-phosphate backbone. In bacteria and eukarya on the other hand, fatty acid side chains are linked via an ester bond to the sn-glycerol-3-phosphate backbone. The polar head groups are globally shared in the three domains of life. The unique membrane lipids of archaea have been implicated not only in the survival and adaptation of the organisms to extreme environments but also to form the basis of the membrane composition of the last universal common ancestor (LUCA. In nature, a diverse range of archaeal lipids is found, the most common are the diether (or archaeol and the tetraether (or caldarchaeol lipids that form a monolayer. Variations in chain length, cyclization and other modifications lead to diversification of these lipids. The biosynthesis of these lipids is not yet well understood however progress in the last decade has led to a comprehensive understanding of the biosynthesis of archaeol. This review describes the current knowledge of the biosynthetic pathway of archaeal ether lipids; insights on the stability and robustness of archaeal lipid membranes; and evolutionary aspects of the lipid divide and the last universal common ancestor LUCA. It examines recent advances made in the field of pathway reconstruction in bacteria.

  15. Ballistic impact response of lipid membranes.

    Science.gov (United States)

    Zhang, Yao; Meng, Zhaoxu; Qin, Xin; Keten, Sinan

    2018-03-08

    Therapeutic agent loaded micro and nanoscale particles as high-velocity projectiles can penetrate cells and tissues, thereby serving as gene and drug delivery vehicles for direct and rapid internalization. Despite recent progress in developing micro/nanoscale ballistic tools, the underlying biophysics of how fast projectiles deform and penetrate cell membranes is still poorly understood. To understand the rate and size-dependent penetration processes, we present coarse-grained molecular dynamics simulations of the ballistic impact of spherical projectiles on lipid membranes. Our simulations reveal that upon impact, the projectile can pursue one of three distinct pathways. At low velocities below the critical penetration velocity, projectiles rebound off the surface. At intermediate velocities, penetration occurs after the projectile deforms the membrane into a tubular thread. At very high velocities, rapid penetration occurs through localized membrane deformation without tubulation. Membrane tension, projectile velocity and size govern which phenomenon occurs, owing to their positive correlation with the reaction force generated between the projectile and the membrane during impact. Two critical membrane tension values dictate the boundaries among the three pathways for a given system, due to the rate dependence of the stress generated in the membrane. Our findings provide broad physical insights into the ballistic impact response of soft viscous membranes and guide design strategies for drug delivery through lipid membranes using micro/nanoscale ballistic tools.

  16. Molecular Transport Studies Through Unsupported Lipid Membranes

    Science.gov (United States)

    Rock, William; Parekh, Sapun; Bonn, Mischa

    2014-03-01

    Dendrimers, spherical polymeric nanoparticles made from branched monomers around a central core, show great promise as drug delivery vehicles. Dendrimer size, core contents, and surface functionality can be synthetically tuned, providing unprecedented versatility. Polyamidoamine (PAMAM) dendrimers have been shown to enter cells; however, questions remain about their biophysical interactions with the cell membrane, specifically about the presence and size of transient pores. We monitor dendrimer-lipid bilayer interactions using unsupported black lipid membranes (BLMs) as model cell membranes. Custom bilayer slides contain two vertically stacked aqueous chambers separated by a 25 μm Teflon sheet with a 120 μm aperture where the bilayer is formed. We vary the composition of model membranes (cholesterol content and lipid phase) to create biomimetic systems and study the interaction of PAMAM G6 and G3 dendrimers with these bilayers. Dendrimers, dextran cargo, and bilayers are monitored and quantified using time-lapse fluorescence imaging. Electrical capacitance measurements are simultaneously recorded to determine if the membrane is porous, and the pore size is deduced by monitoring transport of fluorescent dextrans of increasing molecular weight. These experiments shed light on the importance of cholesterol content and lipid phase on the interaction of dendrimer nanoparticles with membranes.

  17. Membrane-spanning lipids for an uncompromised monitoring of membrane fusion and intermembrane lipid transfer

    Science.gov (United States)

    Schwarzmann, Günter; Breiden, Bernadette; Sandhoff, Konrad

    2015-01-01

    A Förster resonance energy transfer-based fusion and transfer assay was developed to study, in model membranes, protein-mediated membrane fusion and intermembrane lipid transfer of fluorescent sphingolipid analogs. For this assay, it became necessary to apply labeled reporter molecules that are resistant to spontaneous as well as protein-mediated intermembrane transfer. The novelty of this assay is the use of nonextractable fluorescent membrane-spanning bipolar lipids. Starting from the tetraether lipid caldarchaeol, we synthesized fluorescent analogs with fluorophores at both polar ends. In addition, we synthesized radioactive glycosylated caldarchaeols. These labeled lipids were shown to stretch through bilayer membranes rather than to loop within a single lipid layer of liposomes. More important, the membrane-spanning lipids (MSLs) in contrast to phosphoglycerides proved to be nonextractable by proteins. We could show that the GM2 activator protein (GM2AP) is promiscuous with respect to glycero- and sphingolipid transfer. Saposin (Sap) B also transferred sphingolipids albeit with kinetics different from GM2AP. In addition, we could unambiguously show that the recombinant activator protein Sap C x His6 induced membrane fusion rather than intermembrane lipid transfer. These findings showed that these novel MSLs, in contrast with fluorescent phosphoglycerolipids, are well suited for an uncompromised monitoring of membrane fusion and intermembrane lipid transfer. PMID:26269359

  18. Membrane-spanning lipids for an uncompromised monitoring of membrane fusion and intermembrane lipid transfer.

    Science.gov (United States)

    Schwarzmann, Günter; Breiden, Bernadette; Sandhoff, Konrad

    2015-10-01

    A Förster resonance energy transfer-based fusion and transfer assay was developed to study, in model membranes, protein-mediated membrane fusion and intermembrane lipid transfer of fluorescent sphingolipid analogs. For this assay, it became necessary to apply labeled reporter molecules that are resistant to spontaneous as well as protein-mediated intermembrane transfer. The novelty of this assay is the use of nonextractable fluorescent membrane-spanning bipolar lipids. Starting from the tetraether lipid caldarchaeol, we synthesized fluorescent analogs with fluorophores at both polar ends. In addition, we synthesized radioactive glycosylated caldarchaeols. These labeled lipids were shown to stretch through bilayer membranes rather than to loop within a single lipid layer of liposomes. More important, the membrane-spanning lipids (MSLs) in contrast to phosphoglycerides proved to be nonextractable by proteins. We could show that the GM2 activator protein (GM2AP) is promiscuous with respect to glycero- and sphingolipid transfer. Saposin (Sap) B also transferred sphingolipids albeit with kinetics different from GM2AP. In addition, we could unambiguously show that the recombinant activator protein Sap C x His6 induced membrane fusion rather than intermembrane lipid transfer. These findings showed that these novel MSLs, in contrast with fluorescent phosphoglycerolipids, are well suited for an uncompromised monitoring of membrane fusion and intermembrane lipid transfer. Copyright © 2015 by the American Society for Biochemistry and Molecular Biology, Inc.

  19. Amelioration of ionizing radiation induced lipid peroxidation in mouse liver by Moringa oleifera Lam. leaf extract

    International Nuclear Information System (INIS)

    Sinha, Mahuya; Das, Dipesh Kr; Dey, Sanjit; Datta, Sanjukta; Ghosh, Santinath

    2012-01-01

    Protective effect of Moringa oleifera leaf extract (MoLE) against radiation-induced lipid peroxidation has been investigated. Swiss albino mice, selected from an inbred colony, were administered with MoLE (300 mg/kg body wt) for 15 days before exposing to a single dose of 5 Gy 60 Co-gamma radiation. After treatments, animals were necropsied at different post irradiation intervals (days 1, 7 and 15) and hepatic lipid peroxidation and reduced glutathione (GSH) contents were estimated to observe the relative changes due to irradiation and its possible amelioration by MoLE. It was observed that, MoLE treatment restored GSH in liver and prevented radiation induced augmentation in hepatic lipid peroxidation. Phytochemical analysis showed that MoLE possess various phytochemicals such as ascorbic acid, phenolics (catechin, epicatechin, ferulic acid, ellagic acid, myricetin) etc., which may play the key role in prevention of hepatic lipid peroxidation by scavenging radiation induced free radicals. (author)

  20. Protective role of edible clam Paphia malabarica (Chemnitz) against lipid peroxidation and free radicals

    Digital Repository Service at National Institute of Oceanography (India)

    Pawar, R.T.; Nagvenkar, S.S.; Jagtap, T.G.

    In vitro inhibition of lipid peroxidation and free radical scavenging properties of a seafood Paphia malabarica (Chemnitz) as a natural source of antioxidants was observed. Antioxidant activities of Paphia malabarica extracts were tested...

  1. Glutathione protects liver and kidney tissue from cadmium- and lead-provoked lipid peroxidation

    Directory of Open Access Journals (Sweden)

    Jovanović Jasmina M.

    2013-01-01

    Full Text Available Cd and Pb represent a serious ecological problem due to their soluble nature, their mobility and ability to accumulate in the soil. The exposure to these heavy metals can originate from different sources (drinking water, food, air, and they can make their way into the human body through the respiratory and digestive system. We investigated the effects of glutathione on Cd and Pb accumulation and lipid peroxidation effects in the liver and kidneys of heavy metal intoxicated rats. The content of the marker of lipid peroxidation - malondialdehyde was increased several fold the in tissues of exposed animals, the effects being more pronounced in liver. The treatment of intoxicated animals with glutathione drastically suppressed lipid peroxidation. Our results imply that the application of glutathione may have protective role in heavy metal intoxication by inhibiting lipid peroxidation. However, precaution should be made when it comes to Cd, since it seems that glutathione promoted Cd accumulation in the liver.

  2. ROLE OF MEMBRANE LIPID-COMPOSITION IN THE CYTOTOXICITY OF THE SESQUITERPENE LACTONE EUPATORIOPICRIN

    NARCIS (Netherlands)

    VANDERLINDE, JCC; WOERDENBAG, HJ; MALINGRE, TM; KAMPINGA, HH; KONINGS, AWT

    1993-01-01

    The aim of the present study was to investigate a possible role of lipid peroxidation in the cytotoxicity of eupatoriopicrin, the principal sesquiterpene lactone from Eupatorum cannabinum L. Incorporation of arachidonic acid acyl chains in the phospholipids of cellular membranes of mouse fibroblast

  3. Inhibition of lipid peroxidation induced by γ- radiation and AAPH in rat liver and brain mitochondria by mushrooms

    International Nuclear Information System (INIS)

    Lakshmi, B.; Janardhanan, K.K.; Tilak, J.C.; Devasagayam, T.P.A.; Adhikari, S.

    2005-01-01

    Exposure to radiation or 2.2' Azobis(2-amidopropane) dihydrochloride (AAPH) induces generation of reactive oxygen species (ROS) especially hydroxyl radical ( . OH) and peroxyl radical (ROO . ), which are capable of inducing lipid peroxidation. Our earlier studies have demonstrated that extracts of the medicinal and edible mushrooms Ganoderma lucidum, Pleurotus florida, Pleurotus sajor-caju and Phellinus rimosus possessed significant antioxidant activity, measured as radical scavenging. In the present study, we examined the protective effect of these mushroom extracts against radiation- and AAPH-induced lipid peroxidation using rat liver and brain mitochondria as model systems. The results obtained showed that the investigated mushroom extracts significantly inhibited the formation of lipid hydroperoxide and thiobarbituric acid reactive substances, indicating membrane protective effects. The finding suggests the profound protective effect of the extracts of the fruiting bodies of G. lucidum, P. florida, P. sajor-caju and P. rimosus against lipid peroxidation by two major forms of ROS capable of inducing this type of damage in a major organelle, the mitochondria from both rat liver and brain. This observation can possibly explain the health benefits of these mushrooms. (author)

  4. Studies on antibacterial activity of ZnO nanoparticles by ROS induced lipid peroxidation.

    Science.gov (United States)

    Dutta, R K; Nenavathu, Bhavani P; Gangishetty, Mahesh K; Reddy, A V R

    2012-06-01

    Recent studies indicated the role of ROS toward antibacterial activity. In our study we report ROS mediated membrane lipid oxidation of Escherichia coli treated with ZnO nanoparticles (NPs) as supported by detection and spectrophotometric measurement of malondialdehyde (MDA) by TBARS (thiobarbituric acid-reactive species) assay. The antibacterial effects of ZnO NPs were studied by measuring the growth curve of E. coli, which showed concentration dependent bacteriostatic and bacteriocidal effects of ZnO NPs. The antibacterial effects were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Further, antibacterial effect of ZnO NPs was found to decrease by introducing histidine to the culture medium treated with ZnO NPs. The ROS scavenging action of histidine was confirmed by treating histidine to the batch of Escherichia coli+ZnO NPs at the end of the lag phase of the growth curve (Set-I) and during inoculation (Set-II). A moderate bacteriostatic effect (lag in the E. coli growth) was observed in Set-II batch while Set-I showed no bacteriostatic effect. From these evidences we confirmed that the antibacterial effect of bare as well as TG capped ZnO NPs were due to membrane lipid peroxidation caused by the ROS generated during ZnO NPs interaction in culture medium. Copyright © 2012 Elsevier B.V. All rights reserved.

  5. Effect of ethanol and the catalase inhibitor aminotriazole on lipid peroxidation in the rat myocardium

    International Nuclear Information System (INIS)

    Panchenko, L.F.; Pirozhkov, S.V.; Popova, S.V.; Antonenkov, V.D.

    1987-01-01

    The authors study the effect of chronic administration of ethanol and aminotriazole on the level of lipid peroxidation in the ray myocardium. The action of natural and artificial antioxidants on alcohol-induced lipid peroxidation also was studied. To determine the level of chemiluminescence, 1 ml of a sample of nuclear free homogenate or of the total fraction of particles was introduced for radioactivity measurement. After incubation the spontaneous weak luminescence was measured

  6. Atomistic Monte Carlo simulation of lipid membranes

    DEFF Research Database (Denmark)

    Wüstner, Daniel; Sklenar, Heinz

    2014-01-01

    Biological membranes are complex assemblies of many different molecules of which analysis demands a variety of experimental and computational approaches. In this article, we explain challenges and advantages of atomistic Monte Carlo (MC) simulation of lipid membranes. We provide an introduction...... into the various move sets that are implemented in current MC methods for efficient conformational sampling of lipids and other molecules. In the second part, we demonstrate for a concrete example, how an atomistic local-move set can be implemented for MC simulations of phospholipid monomers and bilayer patches...

  7. Sex-related differences in NADPH-dependent lipid peroxidation induced by cadmium

    Energy Technology Data Exchange (ETDEWEB)

    Sato, Masao; Nagai, Yasushi

    1986-10-01

    Male and female rats were dosed once a day for 2 days with injections of 1.5 mg Cd/kg. Formation of thiobarbituric acid reactive substances (TBA-RS) was significantly increased in male rat liver but not in the females. NADPH-dependent lipid peroxidation in vitro in microsomes derived from untreated rat liver was greater in males than in females. Furthermore, addition of cadmium (Cd) to microsomes isolated from male rat liver produced a dose-dependent potentiation of NADPH-dependent lipid peroxidation from low concentrations of CD. In microsomes derived from females a significant increase in lipid peroxidation was observed only at high Cd concentrations. NADPH-dependent lipid peroxidation enhanced by Cd was greater in the males than in the females. These data suggest that a sex-related difference in the ability of Cd to induce lipid peroxidation in vivo in rat liver appears to be mediated partly through differences in hepatic microsomal NADPH-dependent lipid peroxidation.

  8. Induction of lipid peroxidation in erythrocytes during cholesterol oxidation catalyzed by cholesterol oxidase

    International Nuclear Information System (INIS)

    Kagan, V.E.; Monovich, O.; Ribarov, S.R.

    1986-01-01

    The authors study the ability of cholesterol oxidase (ChO), which catalyzes oxidation of cholesterol (Ch) to cholest-4-en-3-one and, at the same time, reduction of O 2 to H 2 O 2 , to induce the lipid peroxidation (LPO) in plasma membranes. Erythrocyte ghosts were obtained from guinea pig blood; the reaction of oxidation of Ch in the erythrocyte ghosts or in micelles with Triton X-100 was carried out in the following medium: Tris-HCl 0.2 M, pH 7.0 (at 37 C), Triton X-100 0.25%, and ChO 0.05 U/ml. At the present time ChO is often used to study the asymmetry of distribution of Ch in biomembranes and the velocity of its transbilayer migration. It is suggested that changes in membrane permeability do not take place during the reaction catalyzed by the enzyme, and no products capable of affecting flip-flop in biological are formed. Accumulation of LPO products in erythrocyte membranes discovered in this investigation under the influence of ChO compels critical re-examination of the resutls

  9. The Fungicidal Activity of Thymol against Fusarium graminearum via Inducing Lipid Peroxidation and Disrupting Ergosterol Biosynthesis

    Directory of Open Access Journals (Sweden)

    Tao Gao

    2016-06-01

    Full Text Available Thymol is a natural plant-derived compound that has been widely used in pharmaceutical and food preservation applications. However, the antifungal mechanism for thymol against phytopathogens remains unclear. In this study, we identified the antifungal action of thymol against Fusarium graminearum, an economically important phytopathogen showing severe resistance to traditional chemical fungicides. The sensitivity of thymol on different F. graminearum isolates was screened. The hyphal growth, as well as conidial production and germination, were quantified under thymol treatment. Histochemical, microscopic, and biochemical approaches were applied to investigate thymol-induced cell membrane damage. The average EC50 value of thymol for 59 F. graminearum isolates was 26.3 μg·mL−1. Thymol strongly inhibited conidial production and hyphal growth. Thymol-induced cell membrane damage was indicated by propidium iodide (PI staining, morphological observation, relative conductivity, and glycerol measurement. Thymol induced a significant increase in malondialdehyde (MDA concentration and a remarkable decrease in ergosterol content. Taken together, thymol showed potential antifungal activity against F. graminearum due to the cell membrane damage originating from lipid peroxidation and the disturbance of ergosterol biosynthesis. These results not only shed new light on the antifungal mechanism of thymol, but also imply a promising alternative for the control of Fusarium head blight (FHB disease caused by F. graminearum.

  10. The effect of ghee (clarified butter) on serum lipid levels and microsomal lipid peroxidation.

    Science.gov (United States)

    Sharma, Hari; Zhang, Xiaoying; Dwivedi, Chandradhar

    2010-04-01

    Ghee, also known as clarified butter, has been utilized for thousands of years in Ayurveda as a therapeutic agent. In ancient India, ghee was the preferred cooking oil. In the last several decades, ghee has been implicated in the increased prevalence of coronary artery disease (CAD) in Asian Indians due to its content of saturated fatty acids and cholesterol and, in heated ghee, cholesterol oxidation products. Our previous research on Sprague-Dawley outbred rats, which serve as a model for the general population, showed no effect of 5 and 10% ghee-supplemented diets on serum cholesterol and triglycerides. However, in Fischer inbred rats, which serve as a model for genetic predisposition to diseases, results of our previous research showed an increase in serum total cholesterol and triglyceride levels when fed a 10% ghee-supplemented diet. In the present study, we investigated the effect of 10% dietary ghee on microsomal lipid peroxidation, as well as serum lipid levels in Fischer inbred rats to assess the effect of ghee on free radical mediated processes that are implicated in many chronic diseases including cardiovascular disease. Results showed that 10% dietary ghee fed for 4 weeks did not have any significant effect on levels of serum total cholesterol, but did increase triglyceride levels in Fischer inbred rats. Ghee at a level of 10% in the diet did not increase liver microsomal lipid peroxidation or liver microsomal lipid peroxide levels. Animal studies have demonstrated many beneficial effects of ghee, including dose-dependent decreases in serum total cholesterol, low density lipoprotein (LDL), very low density lipoprotein (VLDL), and triglycerides; decreased liver total cholesterol, triglycerides, and cholesterol esters; and a lower level of nonenzymatic-induced lipid peroxidation in liver homogenate. Similar results were seen with heated (oxidized) ghee which contains cholesterol oxidation products. A preliminary clinical study showed that high doses of

  11. Atomistic Monte Carlo Simulation of Lipid Membranes

    Directory of Open Access Journals (Sweden)

    Daniel Wüstner

    2014-01-01

    Full Text Available Biological membranes are complex assemblies of many different molecules of which analysis demands a variety of experimental and computational approaches. In this article, we explain challenges and advantages of atomistic Monte Carlo (MC simulation of lipid membranes. We provide an introduction into the various move sets that are implemented in current MC methods for efficient conformational sampling of lipids and other molecules. In the second part, we demonstrate for a concrete example, how an atomistic local-move set can be implemented for MC simulations of phospholipid monomers and bilayer patches. We use our recently devised chain breakage/closure (CBC local move set in the bond-/torsion angle space with the constant-bond-length approximation (CBLA for the phospholipid dipalmitoylphosphatidylcholine (DPPC. We demonstrate rapid conformational equilibration for a single DPPC molecule, as assessed by calculation of molecular energies and entropies. We also show transition from a crystalline-like to a fluid DPPC bilayer by the CBC local-move MC method, as indicated by the electron density profile, head group orientation, area per lipid, and whole-lipid displacements. We discuss the potential of local-move MC methods in combination with molecular dynamics simulations, for example, for studying multi-component lipid membranes containing cholesterol.

  12. Resveratrol suppresses ethanol stress in winery and bottom brewery yeast by affecting superoxide dismutase, lipid peroxidation and fatty acid profile.

    Science.gov (United States)

    Gharwalova, Lucia; Sigler, Karel; Dolezalova, Jana; Masak, Jan; Rezanka, Tomas; Kolouchova, Irena

    2017-11-03

    Mid-exponential cultures of two traditional biotechnological yeast species, winery Saccharomyces cerevisiae and the less ethanol tolerant bottom-fermenting brewery Saccharomyces pastorianus, were exposed to different concentrations of added ethanol (3, 5 and 8%) The degree of ethanol-induced cell stress was assessed by measuring the cellular activity of superoxide dismutase (SOD), level of lipid peroxidation products, changes in cell lipid content and fatty acid profile. The resveratrol as an antioxidant was found to decrease the ethanol-induced rise of SOD activity and suppress the ethanol-induced decrease in cell lipids. A lower resveratrol concentration (0.5 mg/l) even reduced the extent of lipid peroxidation in cells. Resveratrol also alleviated ethanol-induced changes in cell lipid composition in both species by strongly enhancing the proportion of saturated fatty acids and contributing thereby to membrane stabilization. Lower resveratrol concentrations could thus diminish the negative effects of ethanol stress on yeast cells and improve their physiological state. These effects may be utilized to enhance yeast vitality in high-ethanol-producing fermentations or to increase the number of yeast generations in brewery.

  13. Raised concentrations of lipid peroxidation products (LPO in pregnant women with impaired glucose tolerance

    Directory of Open Access Journals (Sweden)

    Krzysztof C. Lewandowski

    2014-06-01

    Full Text Available introduction. Lipid peroxidation (LPO results from oxidative damage to membrane lipids. Whereas LPO rises in normal pregnancy, the effect of gestational diabetes mellitus (GDM on this process has not been clearly defined. materials and method. Fasting blood concentrations of malondialdehyde+4-hydroxyalkenals (MDA+4-HDA, as LPO index, TNFa soluble receptors (sTNF-R1 and sTNF-R2, and soluble adhesion molecules (sICAM-1, sVCAM-1, were measured in 51 women at 28 weeks of gestation. The women were divided according to the results of 50.0 g glucose challenge test (GCT and 75.0 g oral glucose tolerance test (OGTT: Controls (n=20, normal responses to both GCT and OGTT; Intermediate Group (IG (n=15, abnormal GCT but normal OGTT; GDM group (n=16, abnormal both GCT and OGTT. results. Glucose concentrations in women diagnosed with GDM were within the range of impaired glucose tolerance. There were no significant differences in concentrations of either TNF a soluble receptors R1 and R2, or sICAM-1 or sVCAM-1. LPO concentrations [MDA+4-HDA (nmol/mg protein] were significantly higher in women with GDM than in the other two groups [64.1±24.3 (mean±SD, 39.3±23.1, 47.0±18.1, for GDM, IG and Controls, respectively; p<0.05]. In multivariate analysis, the only significant independent correlation was between LPO level and glucose at 120 minutes of OGTT (rs=0.42; p=0.009. conclusions. Oxidative damage to membrane lipids is increased in GDM and might result directly from hyperglycaemia. Physiological significance of this phenomenon remains to be elucidated.

  14. Detection of lipid peroxidation in frozen-thawed avian spermatozoa using C(11)-BODIPY(581/591).

    Science.gov (United States)

    Partyka, Agnieszka; Lukaszewicz, Ewa; Niżański, Wojciech; Twardoń, Jan

    2011-06-01

    The aim of this study was to perform flow cytometric analysis of C11-BODIPY581/591 oxidation in fowl and geese sperm as a marker for membrane lipid peroxidation (LPO) and to establish if the cryopreservation process would make sperm membranes more susceptible to oxidative stress. The experiment was carried out on 10 meat type line Flex roosters and 10 White Koluda® geese. The semen was collected two times a week, by dorso-abdominal massage method and pooled from 10 individuals of each species. Fowl semen samples were subjected to cryopreservation using the "pellet" method and Dimethylacetamide (DMA) as a cryoprotectant. Geese semen samples were cryopreserved in plastic straws in a programmable freezing unit with Dimethyloformamide (DMF) as the cryoprotectant. A fluorescent lipid probe C11-BODIPY581/591 provided with two double bonds that are oxidized during their contact with ROS, was used for the purpose of the assessment of the LPO in freshly diluted semen samples and frozen-thawed semen samples. This probe changes its color according to its state (non peroxidized: red; peroxidized: green). Flow cytometric analysis was used to monitor these changes. The White Koluda® geese fresh semen had a higher level of LPO than the Flex fresh semen (P > 0.01). The cryopreservation of fowl semen significantly (P > 0.01) increased the percentage of live and dead spermatozoa with lipid peroxidation. In frozen-thawed semen of White Koluda® geese the percentage of live spermatozoa with LPO significantly decreased (P > 0.05) whereas significantly (P > 0.01) higher level of dead cells with LPO was observed. There were significant differences between the two studied species. After thawing, the percentage of live and dead spermatozoa with lipid peroxidation was higher in fowl semen than in geese semen (P > 0.01). In conclusion, our data clearly indicate the existence of species specific differences in susceptibility of spermatozoa to the oxidation of PUFAs in the cell membranes

  15. Self-assembled tethered bimolecular lipid membranes.

    Science.gov (United States)

    Sinner, Eva-Kathrin; Ritz, Sandra; Naumann, Renate; Schiller, Stefan; Knoll, Wolfgang

    2009-01-01

    This chapter describes some of the strategies developed in our group for designing, constructing and structurally and functionally characterizing tethered bimolecular lipid membranes (tBLM). We introduce this platform as a novel model membrane system that complements the existing ones, for example, Langmuir monolayers, vesicular liposomal dispersions and bimolecular ("black") lipid membranes. Moreover, it offers the additional advantage of allowing for studies of the influence of membrane structure and order on the function of integral proteins, for example, on how the composition and organization of lipids in a mixed membrane influence the ion translocation activity of integral channel proteins. The first strategy that we introduce concerns the preparation of tethered monolayers by the self-assembly of telechelics. Their molecular architecture with a headgroup, a spacer unit (the "tether") and the amphiphile that mimics the lipid molecule allows them to bind specifically to the solid support thus forming the proximal layer of the final architecture. After fusion of vesicles that could contain reconstituted proteins from a liposomal dispersion in contact to this monolayer the tethered bimolecular lipid membrane is obtained. This can then be characterized by a broad range of surface analytical techniques, including surface plasmon spectroscopies, the quartz crystal microbalance, fluorescence and IR spectroscopies, and electrochemical techniques, to mention a few. It is shown that this concept allows for the construction of tethered lipid bilayers with outstanding electrical properties including resistivities in excess of 10 MOmega cm2. A modified strategy uses the assembly of peptides as spacers that couple covalently via their engineered sulfhydryl or lipoic acid groups at the N-terminus to the employed gold substrate, while their C-terminus is being activated afterward for the coupling of, for example, dimyristoylphosphatidylethanol amine (DMPE) lipid molecules

  16. Interaction of Hematoporphyrin with Lipid Membranes

    DEFF Research Database (Denmark)

    Stepniewski, M.; Kepczynski, M.; Jamroz, D.

    2012-01-01

    Natural or synthetic porphyrins are being used as photosensitizers in photodiagnosis (PD) and photodynamic therapy (PDT) of malignancies and some other diseases. Understanding the interactions between porphyrins and cell membranes is therefore important to rationalize the uptake of photosensitizers...... and their passive transport through cell membranes. In this study, we consider the properties of hematoporphyrin (Hp), a well-known photosensitizer for PD and PDT, in the presence of a 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) bilayer that we use as a model system for protein-free cell membranes....... The dianions, being in the aqueous phase, formed stable dimers with a strictly determined geometry. Our results fully supported the experimental data and provide a more detailed molecular-level description of the interactions of photosensitizers with lipid membranes....

  17. Ecklonia cava Extract and Dieckol Attenuate Cellular Lipid Peroxidation in Keratinocytes Exposed to PM10.

    Science.gov (United States)

    Lee, Jeong-Won; Seok, Jin Kyung; Boo, Yong Chool

    2018-01-01

    Airborne particulate matter can cause oxidative stress, inflammation, and premature skin aging. Marine plants such as Ecklonia cava Kjellman contain high amounts of polyphenolic antioxidants. The purpose of this study was to examine the antioxidative effects of E. cava extract in cultured keratinocytes exposed to airborne particulate matter with a diameter of <10  μ m (PM10). After the exposure of cultured HaCaT keratinocytes to PM10 in the absence and presence of E. cava extract and its constituents, cell viability and cellular lipid peroxidation were assessed. The effects of eckol and dieckol on cellular lipid peroxidation and cytokine expression were examined in human epidermal keratinocytes exposed to PM10. The total phenolic content of E. cava extract was the highest among the 50 marine plant extracts examined. The exposure of HaCaT cells to PM10 decreased cell viability and increased lipid peroxidation. The PM10-induced cellular lipid peroxidation was attenuated by E. cava extract and its ethyl acetate fraction. Dieckol more effectively attenuated cellular lipid peroxidation than eckol in both HaCaT cells and human epidermal keratinocytes. Dieckol and eckol attenuated the expression of inflammatory cytokines such as tumor necrosis factor- (TNF-) α , interleukin- (IL-) 1 β , IL-6, and IL-8 in human epidermal keratinocytes stimulated with PM10. This study suggested that the polyphenolic constituents of E. cava , such as dieckol, attenuated the oxidative and inflammatory reactions in skin cells exposed to airborne particulate matter.

  18. Induction of antioxidant enzyme activity and lipid peroxidation level in ion-beam-bombarded rice seeds

    Science.gov (United States)

    Semsang, Nuananong; Yu, LiangDeng

    2013-07-01

    Low-energy ion beam bombardment has been used to mutate a wide variety of plant species. To explore the indirect effects of low-energy ion beam on biological damage due to the free radical production in plant cells, the increase in antioxidant enzyme activities and lipid peroxidation level was investigated in ion-bombarded rice seeds. Local rice seeds were bombarded with nitrogen or argon ion beams at energies of 29-60 keV and ion fluences of 1 × 1016 ions cm-2. The activities of the antioxidant enzymes; superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR), glutathione reductase (GR), glutathione S-transferase (GST) and lipid peroxidation level were assayed in the germinated rice seeds after ion bombardment. The results showed most of the enzyme activities and lipid peroxidation levels in both the argon and nitrogen bombarded samples were higher than those in the natural control. N-ion bombardment could induce higher levels of antioxidant enzyme activities in the rice samples than the Ar-ion bombardment. Additional effects due to the vacuum condition were found to affect activities of some antioxidant enzymes and lipid peroxidation level. This study demonstrates that ion beam bombardment and vacuum condition could induce the antioxidant enzyme activity and lipid peroxidation level which might be due to free radical production in the bombarded rice seeds.

  19. Inhibition of rat liver microsomal lipid peroxidation by N-acyldehydroalanines: An in vitro comparative study

    Energy Technology Data Exchange (ETDEWEB)

    Buc-Calderon, P.; Roberfroid, M. (Universite Catholique de Louvain, Brussels (Belgium))

    1989-09-01

    Captodative substituted olefins are radical scavengers which react with free radicals to form stabilized radical adducts. One of those compounds, N-(paramethoxyphenylacetyl)dehydroalanine (AD-5), may react and scavenge both superoxide anion (O-2) and alk-oxyl radicals (RO.), and in this way prevent the appearance of their mediated biological effects. Nitrofurantoin and tert-butyl hydroperoxide were used as model compounds to stimulate free radical production and their mediated lipid peroxidation in rat liver microsomes. In addition, lipid peroxidation was also initiated by exposure of rat liver microsomal suspensions to ionizing radiation (gamma rays). The microsomal lipid peroxidation induced by these chemicals and physical agents was inhibited by the addition of AD-5. These effects were dose-dependent in a millimolar range of concentration. In addition, AD-5 has no effect on microsomal electron transport, showing that NADPH-cytochrome P450 reductase activity was not modified. These data, together with the comparisons of the effects of AD-5 and some antioxidant molecules such as superoxide dismutase, uric acid, and mannitol, support the conclusion that inhibition of lipid peroxidation by AD-5 is the result of its free radical scavenger activity. In addition, the inhibitory effect of AD-5 on microsomal lipid peroxidation was dependent of the nature of the free radical species involved in the initiation of the process, suggesting that O-2 is scavenged more efficiently than RO.

  20. Total antioxidant status and lipid peroxidation with and without in vitro zinc supplementation in infertile men.

    Science.gov (United States)

    Ajina, T; Sallem, A; Haouas, Z; Mehdi, M

    2017-09-01

    The aim of this study was to assess the total antioxidant capacity (TAC) and malondialdehyde (MDA) level in infertile men with asthenozoospermia and asthenoteratozoospermia compared to fertile donors, and to examine the effect of zinc on sperm lipid peroxidation and antioxidant status in infertile and fertile men. Semen samples provided by infertile men (n = 38) and fertile donors (controls; n = 12) were exposed to 6 mmol/L of zinc for 2 hr at 37°C. After semen analysis, lipid peroxidation was detected by MDA assay and seminal TAC was assessed by colorimetric method using TAS (total antioxidant status) Kit. TAC was significantly lower in infertile group compared to controls (p = .037). However, lipid peroxidation did not alter in infertile patients compared to controls (p > .05). After in vitro incubation of samples with zinc, a significant increase in TAC level was found only in infertile men (p zinc had no effect on sperm lipid peroxidation in both fertile and infertile men (p > .05). Our data indicate that antioxidant treatment based on zinc in vitro supplementation may be helpful to enhance the rate of seminal antioxidant status in infertile men; however, it does not prevent sperm lipid peroxidation. © 2016 Blackwell Verlag GmbH.

  1. Anionic lipids and the maintenance of membrane electrostatics in eukaryotes.

    Science.gov (United States)

    Platre, Matthieu Pierre; Jaillais, Yvon

    2017-02-01

    A wide range of signaling processes occurs at the cell surface through the reversible association of proteins from the cytosol to the plasma membrane. Some low abundant lipids are enriched at the membrane of specific compartments and thereby contribute to the identity of cell organelles by acting as biochemical landmarks. Lipids also influence membrane biophysical properties, which emerge as an important feature in specifying cellular territories. Such parameters are crucial for signal transduction and include lipid packing, membrane curvature and electrostatics. In particular, membrane electrostatics specifies the identity of the plasma membrane inner leaflet. Membrane surface charges are carried by anionic phospholipids, however the exact nature of the lipid(s) that powers the plasma membrane electrostatic field varies among eukaryotes and has been hotly debated during the last decade. Herein, we discuss the role of anionic lipids in setting up plasma membrane electrostatics and we compare similarities and differences that were found in different eukaryotic cells.

  2. Binding of Serotonin to Lipid Membranes

    DEFF Research Database (Denmark)

    Peters, Günther H.J.; Wang, Chunhua; Cruys-Bagger, Nicolaj

    2013-01-01

    Serotonin (5-hydroxytryptamine, 5-HT) is a prevalent neurotransmitter throughout the animal kingdom. It exerts its effect through the specific binding to the serotonin receptor, but recent research has suggested that neural transmission may also be affected by its nonspecific interactions...... with the lipid matrix of the synaptic membrane. However, membrane–5-HT interactions remain controversial and superficially investigated. Fundamental knowledge of this interaction appears vital in discussions of putative roles of 5-HT, and we have addressed this by thermodynamic measurements and molecular...... dynamics (MD) simulations. 5-HT was found to interact strongly with lipid bilayers (partitioning coefficient ∼1200 in mole fraction units), and this is highly unusual for a hydrophilic solute like 5-HT which has a bulk, oil–water partitioning coefficient well below unity. It follows that membrane affinity...

  3. Siofor influence on the process of lipid peroxidation and antioxidant status at patients with metabolic syndrome

    Directory of Open Access Journals (Sweden)

    Elena N. Chernysheva

    2014-10-01

    Full Text Available The purpose of the work is to research siofor influence (metformin on the activity of the process of lipid peroxidation and antioxidant activity of blood serum at patients with metabolic syndrome. Material and Methods — 62 patients with metabolic syndrome at the age from 30 till 60 were examined and treated by siofor (1700 mg per day during a year. The process of lipid peroxidation was studied due to the level of lipid hydroperoxide of blood serum. Antioxidant capacity was based on the antioxidant reaction in the blood serum with definite number of exogenic hydrogen dioxide (mkmole/l with the method of enzyme-linked immunosorbent assay (ELISA. Results — Intensification of process of lipid peroxidation has been observed at patients with metabolic syndrome — the level of lipid hydroperoxide of blood serum has been 2.9 (1.9, 3.9 mkM (presented as median and interquartile range, antioxidant activity of blood serum has been decreased — 276.4 (239.0, 379.9 mkmole/l. In 12 months of siofor intake hydroperoxide level has been decreased till 1.1 (0.8, 1.9 mkМ, but antioxidant activity has been increased and amounted 320.0 (278.9, 334.3 mkmole/l. Conclusion — Siofor has been proved to be a highly effective medicine for correction of process of lipid peroxidation and for improvement of antioxidant activity of blood serum at patients with metabolic syndrome.

  4. Importance of the hexagonal lipid phase in biological membrane organisation

    Directory of Open Access Journals (Sweden)

    Juliette eJouhet

    2013-12-01

    Full Text Available Abstract:Domains are present in every natural membrane. They are characterised by a distinctive protein and/or lipid composition. Their size is highly variable from the nano- to the micrometer scale. The domains confer specific properties to the membrane leading to original structure and function. The determinants leading to domain organisation are therefore important but remain obscure. This review presents how the ability of lipids to organize into hexagonal II or lamellar phases can promote particular local structures within membranes. Since biological membranes are composed of a mixture of lipids, each with distinctive biophysical properties, lateral and transversal sorting of lipids can promote creation of domains inside the membrane through local modulation of the lipid phase. Lipid biophysical properties have been characterized for long based on in vitro analyses using non-natural lipid molecules; their re-examinations using natural lipids might open interesting perspectives on membrane architecture occurring in vivo in various cellular and physiological contexts.

  5. Importance of the hexagonal lipid phase in biological membrane organization.

    Science.gov (United States)

    Jouhet, Juliette

    2013-01-01

    Domains are present in every natural membrane. They are characterized by a distinctive protein and/or lipid composition. Their size is highly variable from the nano- to the micrometer scale. The domains confer specific properties to the membrane leading to original structure and function. The determinants leading to domain organization are therefore important but remain obscure. This review presents how the ability of lipids to organize into hexagonal II or lamellar phases can promote particular local structures within membranes. Since biological membranes are composed of a mixture of lipids, each with distinctive biophysical properties, lateral and transversal sorting of lipids can promote creation of domains inside the membrane through local modulation of the lipid phase. Lipid biophysical properties have been characterized for long based on in vitro analyses using non-natural lipid molecules; their re-examinations using natural lipids might open interesting perspectives on membrane architecture occurring in vivo in various cellular and physiological contexts.

  6. Turmeric and black pepper spices decrease lipid peroxidation in meat patties during cooking

    Science.gov (United States)

    Zhang, Yanjun; Henning, Susanne M.; Lee, Ru-Po; Huang, Jianjun; Zerlin, Alona; Li, Zhaoping; Heber, David

    2015-01-01

    Abstract Spices are rich in natural antioxidants and have been shown to be potent inhibitors of lipid peroxidation during cooking of meat. Turmeric contains unique conjugated curcuminoids with strong antioxidant activity. Piperine, one of the main constituents of black pepper, is known to increase the bioavailability of curcuminoids in mouse and human studies when consumed with turmeric. We investigated whether adding black pepper to turmeric powder may further inhibit lipid peroxidation when added to meat patties prior to cooking. The addition of black pepper to turmeric significantly decreased the lipid peroxidation in hamburger meat. When investigating the antioxidant activity of the main chemical markers, we determined that piperine did not exhibit any antioxidant activity. Therefore, we conclude that other black pepper ingredients are responsible for the increased antioxidant activity of combining black pepper with turmeric powder. PMID:25582173

  7. Lipid Peroxidation and Transforming Growth Factor-β1 Levels in Gastric Cancer at Pathologic Stages.

    Science.gov (United States)

    Tüzün, Sefa; Yücel, Ahmet Fikret; Pergel, Ahmet; Kemik, Ahu Sarbay; Kemik, Ozgür

    2012-09-01

    High levels of TGF-β1 and enhanced TGF-β1 receptor signaling are related to the pathology of gastric cancer. This effect is caused by oxidative stress and lipid peroxidation products. The aim of this study was to investigate the levels of TGF-β1 and lipid peroxidation products in gastric cancer patients and their correlation with pathologic stage. Lipid peroxidation products and TGF-β1 levels were studied in the serum samples of 50 gastric cancer patients and 18 control subjects. HNE-protein adducts and TGF-β1 levels were significantly higher in T2, T3 and T4 gastric cancers than in either the T1 stage or controls (p<0.001). Pathologic stage was correlated with TGF-β1 levels (r=0.702, p<0.05). These markers production may contribute to tumor angiogenesis and aid in the prognosis of the gastric cancer.

  8. Membrane Contact Sites: Complex Zones for Membrane Association and Lipid Exchange

    OpenAIRE

    Evan Quon; Christopher T. Beh

    2016-01-01

    Lipid transport between membranes within cells involves vesicle and protein carriers, but as agents of nonvesicular lipid transfer, the role of membrane contact sites has received increasing attention. As zones for lipid metabolism and exchange, various membrane contact sites mediate direct associations between different organelles. In particular, membrane contact sites linking the plasma membrane (PM) and the endoplasmic reticulum (ER) represent important regulators of lipid and ion transfer...

  9. Lipid polymorphism and the functional roles of lipids in biological membranes

    NARCIS (Netherlands)

    Cullis, P.R.; Kruijff, B. de

    1979-01-01

    The reasons for the great variety of lipids found in biological membranes, and the relations between lipid composition and membrane function pose major unsolved problems in membrane biology. Perhaps the only major functional role of lipids which may be regarded as firmly established involves the

  10. Perioperative intravenous acetaminophen attenuates lipid peroxidation in adults undergoing cardiopulmonary bypass: a randomized clinical trial.

    Directory of Open Access Journals (Sweden)

    Frederic T Billings

    Full Text Available Cardiopulmonary bypass (CPB lyses erythrocytes and induces lipid peroxidation, indicated by increasing plasma concentrations of free hemoglobin, F2-isoprostanes, and isofurans. Acetaminophen attenuates hemeprotein-mediated lipid peroxidation, reduces plasma and urine concentrations of F2-isoprostanes, and preserves kidney function in an animal model of rhabdomyolysis. Acetaminophen also attenuates plasma concentrations of isofurans in children undergoing CPB. The effect of acetaminophen on lipid peroxidation in adults has not been studied. This was a pilot study designed to test the hypothesis that acetaminophen attenuates lipid peroxidation in adults undergoing CPB and to generate data for a clinical trial aimed to reduce acute kidney injury following cardiac surgery.In a prospective double-blind placebo-controlled clinical trial, sixty adult patients were randomized to receive intravenous acetaminophen or placebo starting prior to initiation of CPB and for every 6 hours for 4 doses. Acetaminophen concentrations measured 30 min into CPB and post-CPB were 11.9 ± 0.6 μg/mL (78.9 ± 3.9 μM and 8.7 ± 0.3 μg/mL (57.6 ± 2.0 μM, respectively. Plasma free hemoglobin increased more than 15-fold during CPB, and haptoglobin decreased 73%, indicating hemolysis. Plasma and urinary markers of lipid peroxidation also increased during CPB but returned to baseline by the first postoperative day. Acetaminophen reduced plasma isofuran concentrations over the duration of the study (P = 0.05, and the intraoperative plasma isofuran concentrations that corresponded to peak hemolysis were attenuated in those subjects randomized to acetaminophen (P = 0.03. Perioperative acetaminophen did not affect plasma concentrations of F2-isoprostanes or urinary markers of lipid peroxidation.Intravenous acetaminophen attenuates the increase in intraoperative plasma isofuran concentrations that occurs during CPB, while urinary markers were unaffected.ClinicalTrials.gov NCT

  11. Induction of antioxidant enzyme activity and lipid peroxidation level in ion-beam-bombarded rice seeds

    Energy Technology Data Exchange (ETDEWEB)

    Semsang, Nuananong, E-mail: nsemsang@gmail.com [Molecular Biology Laboratory, Department of Biology, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Yu, LiangDeng [Plasma and Beam Physics Research Facility, Department of Physics and Materials Science, Faculty of Science, Chiang Mai University, Chiang Mai 50200 (Thailand); Thailand Center of Excellence in Physics, Commission on Higher Education, 328 Si Ayutthaya Road, Bangkok 10400 (Thailand)

    2013-07-15

    Highlights: ► Ion beam bombarded rice seeds in vacuum. ► Studied seed survival from the ion bombardment. ► Determined various antioxidant enzyme activities and lipid peroxidation level. ► Discussed vacuum, ion species and ion energy effects. ► Attributed the changes to free radical formation due to ion bombardment. -- Abstract: Low-energy ion beam bombardment has been used to mutate a wide variety of plant species. To explore the indirect effects of low-energy ion beam on biological damage due to the free radical production in plant cells, the increase in antioxidant enzyme activities and lipid peroxidation level was investigated in ion-bombarded rice seeds. Local rice seeds were bombarded with nitrogen or argon ion beams at energies of 29–60 keV and ion fluences of 1 × 10{sup 16} ions cm{sup −2}. The activities of the antioxidant enzymes; superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APX), dehydroascorbate reductase (DHAR), glutathione reductase (GR), glutathione S-transferase (GST) and lipid peroxidation level were assayed in the germinated rice seeds after ion bombardment. The results showed most of the enzyme activities and lipid peroxidation levels in both the argon and nitrogen bombarded samples were higher than those in the natural control. N-ion bombardment could induce higher levels of antioxidant enzyme activities in the rice samples than the Ar-ion bombardment. Additional effects due to the vacuum condition were found to affect activities of some antioxidant enzymes and lipid peroxidation level. This study demonstrates that ion beam bombardment and vacuum condition could induce the antioxidant enzyme activity and lipid peroxidation level which might be due to free radical production in the bombarded rice seeds.

  12. Protein conjugated with aldehydes derived from lipid peroxidation as an independent parameter of the carbonyl stress in the kidney damage

    Directory of Open Access Journals (Sweden)

    Medina-Navarro Rafael

    2011-11-01

    Full Text Available Abstract Background One of the well-defined and characterized protein modifications usually produced by oxidation is carbonylation, an irreversible non-enzymatic modification of proteins. However, carbonyl groups can be introduced into proteins by non-oxidative mechanisms. Reactive carbonyl compounds have been observed to have increased in patients with renal failure. In the present work we have described a procedure designed as aldehyde capture to calculate the protein carbonyl stress derived solely from lipid peroxidation. Methods Acrolein-albumin adduct was prepared as standard at alkaline pH. Rat liver microsomal membranes and serum samples from patients with diabetic nephropathy were subjected to the aldehyde capture procedure and aldol-protein formation. Before alkalinization and incubation, samples were precipitated and redisolved in 6M guanidine. The absorbances of the samples were read with a spectrophotometer at 266 nm against a blank of guanidine. Results Evidence showed abundance of unsaturated aldehydes derived from lipid peroxidation in rat liver microsomal membranes and in the serum of diabetic patients with advanced chronic kidney disease. Carbonyl protein and aldol-proteins resulted higher in the diabetic nephropathy patients (p Conclusion The aldehyde-protein adduct represents a non oxidative component of carbonyl stress, independent of the direct amino acid oxidation and could constitute a practical and novelty strategy to measure the carbonyl stress derived solely from lipid peroxidation and particularly in diabetic nephropathy patients. In addition, we are in a position to propose an alternative explanation of why alkalinization of urine attenuates rhabdomyolysis-induced renal dysfunction.

  13. Protective effects of Opuntia ficus-indica extract on ram sperm quality, lipid peroxidation and DNA fragmentation during liquid storage.

    Science.gov (United States)

    Allai, Larbi; Druart, Xavier; Öztürk, Mehmet; BenMoula, Anass; Nasser, Boubker; El Amiri, Bouchra

    2016-12-01

    The present study aimed to assess the phenolic composition of the acetone extract from Opuntia ficus indica cladodes (ACTEX) and its effects on ram semen variables, lipid peroxidation and DNA fragmentation during liquid storage at 5°C for up to 72h in skim milk and Tris egg yolk extenders. Semen samples from five rams were pooled extended with Tris-egg yolk (TEY) or skim milk (SM) extenders containing ACTEX (0%, 1%, 2%, 4% and 8%) at a final concentration of 0.8×10 9 sperm/ml and stored for up to 72h at 5°C. The sperm variables were evaluated at different time periods (8, 24, 48 and 72h). Sperm total motility and viability were superior in TEY than in SM whereas the progressive motility, membrane integrity, abnormality and spontaneous lipid peroxidation were greater in SM compared to TEY (P<0.05). The results also indicated that the inclusion of 1% ACTEX in the SM or TEY extender increased the sperm motility, viability, membrane integrity, and decreased the abnormality, lipids peroxidation up to 72h in storage compared to control group. Similarly, even at 72h of storage, 1% ACTEX can efficiently decrease the negative effects of liquid storage on sperm DNA fragmentation (P<0.05). In conclusion, SM and TEY supplemented with 1% of ACTEX can improve the quality of ram semen. Further studies are required to identify the active components in ACTEX involved in its effect on ram sperm preservation. Copyright © 2016 Elsevier B.V. All rights reserved.

  14. Radiation-induced lipid peroxidation, fish diet, and modulation of the effects by vitamin E

    International Nuclear Information System (INIS)

    Paranich, A.V.; Chajkina, L.A.; Zharkov, S.V.

    1990-01-01

    Data are presented in this paper on the effect of vitamin E on rats given a fish diet after whole-body gamma-irradiation. The content of lipid peroxidation products in rat plasma, brain and liver and also content of vitamin E have been investigated. Irradiation increases lipid peroxidation in the studied tissues and decreases vitamin E content. This process is aggravat ed by the fish diet. Vitamin E given in addition to fish diet helps the organism to stabilize the antioxidant homeostasis at a qualitatively different level

  15. Involvement of active oxygen in lipid peroxide radical reaction of epidermal homogenate following ultraviolet light exposure

    International Nuclear Information System (INIS)

    Nishi, J.; Ogura, R.; Sugiyama, M.; Hidaka, T.; Kohno, M.

    1991-01-01

    To elucidate the radical mechanism of lipid peroxidation induced by ultraviolet light (UV) irradiation, an electron spin resonance (ESR) study was made on epidermal homogenate prepared from albino rat skin. The exposure of the homogenate to UV light resulted in an increase in lipid peroxide content, which was proportional to the time of UV exposure. Using ESR spin trapping (dimethyl-1-pyrroline-N-oxide, DMPO), the DMPO spin adduct spectrum of lipid radicals (L.) was measured following UV exposure (DMPO-L.:aN = 15.5 G, aH = 22.7 G), as was the spectrum of DMPO-hydroxyl radical (DMPO-OH, aN = aH = 15.5 G). In the presence of superoxide dismutase, the DMPO spin adduct spectrum of lipid radicals was found to be reduced remarkably. Therefore, it was shown that the generation of the lipid radicals partially involves superoxide anion radicals, in addition to hydroxyl radicals. In the ESR free-radical experiment, an ESR signal appeared at g = 2.0064 when the ESR tube filled with homogenate was exposed to UV light at -150 degrees C. The temperature-dependent change in the ESR free radical signal of homogenate exposed to UV light was observed at temperatures varying from -150 degrees C to room temperature. By using degassed samples, it was confirmed that oxygen is involved in the formation of the lipid peroxide radicals (LOO.) from the lipid radicals (L.)

  16. Effect of irradiation on lipid peroxidation in serum, 1

    International Nuclear Information System (INIS)

    Haisa, Yoshio

    1975-01-01

    Rabbits were irradiated once with 1000R over the whole body, and the following results were obtained. 1) The whole lipid content of serum: The whole lipid content was found to have increased about 2.6 times 24 hours after irradiation, and even after a lapse of 48 hours such a tendency persisted. 2) Serum whole TBA level: 24 hours after irradiation the whole TBA level had increased markedly up to about 6.5-fold of that before irradiation. 3) Lipid content of fraction: Especially marked in the increase in triglyceride. 4) TBA level of fractionated lipid: There is seen a marked increase in cholesterol ester, which practically occupied the entire serum TBA value. Next marked was the increase in phospholipid, and quantitatively it was classified that the increases seen in triglyceride and free fatty acids are not concerned with the rise in the free fatty acid content and TBA level. 5) Serum lipid contents and TBA level in fasting: By taking the level of serum lipid 24 hours after the start of fasting as one, the serum lipid levels were studied at 48 and 72 hours after the start of fasting, and it was found that both serum lipid and TBA levels rose only very slightly. 6) Changes in fatty acids: The relative ratio of palmitic acid to the whole fatty acids increased after irradiation, and the ratios of linolic acid and linolenic acid were decreased by irradiation while by 48 hours the relative ratio of linolic acid was decreased to about 1/5 of that before irradiation, and the relative ratio of linolenic acid was markedly decreased to about 1/35. (JPN)

  17. Study of lipid profile and parieto-temporal lipid peroxidation in AlCl3 mediated neurotoxicity. modulatory effect of fenugreek seeds

    Directory of Open Access Journals (Sweden)

    Belaïd-Nouira Yosra

    2012-01-01

    Full Text Available Abstract Background Peroxidation of lipid (LPO membrane and cholesterol metabolism have been involved in the physiopathology of many diseases of aging brain. Therefore, this prospective animal study was carried firstly to find out the correlation between LPO in posterior brain and plasmatic cholesterol along with lipoprotein levels after chronic intoxication by aluminium chloride (AlCl3. Chronic aluminum-induced neurotoxicity has been in fact related to enhanced brain lipid peroxidation together with hypercholesterolemia and hypertriglyceridemia, despite its controversial etiological role in neurodegenerative diseases. Secondly an evaluation of the effectiveness of fenugreek seeds in alleviating the engendered toxicity through these biochemical parameters was made. Results Oral administration of AlCl3 to rats during 5 months (500 mg/kg bw i.g for one month then 1600 ppm via the drinking water enhanced the levels of LPO in posterior brain, liver and plasma together with lactate dehydrogenase (LDH activities, total cholesterol (TC, triglycerides (TG and LDL-C (Low Density Lipoproteins levels. All these parameters were decreased following fenugreek seeds supplementation either as fenugreek seed powder (FSP or fenugreek seed extract (FSE. A notable significant correlation was observed between LPObrain and LDL-C on one hand and LDHliver on the other hand. This latter was found to correlate positively with TC, TG and LDL-C. Furthermore, high significant correlations were observed between LDHbrain and TC, TG, LDL-C, LPObrain as well as LDHliver. Conclusion Aluminium-induced LPO in brain could arise from alteration of lipid metabolism particularly altered lipoprotein metabolism rather than a direct effect of cholesterol oxidation. Fenugreek seeds could play an anti-peroxidative role in brain which may be attributed in part to its modulatory effect on plasmatic lipid metabolism.

  18. Effect of Cryphonectria parasitica toxin on lipid peroxidation and ...

    African Journals Online (AJOL)

    Jane

    2011-10-24

    Oct 24, 2011 ... on membrane systems of the cells were lighter and they occurred later than expected ... those of the control (P<0.01), while the plasma membrane and cell wall broke ... toxic metabolites and phytotoxins, and they induce plant.

  19. The results of the lipids peroxidation products on the DNA bases as biological markers of the oxidative stress; Les adduits des produits de la peroxydation lipidique sur les bases de l'ADN comme biomarqueurs du stress oxydant

    Energy Technology Data Exchange (ETDEWEB)

    Falletti, O

    2007-10-15

    Different ways of DNA damages have been studied, among these ones the direct way of DNA damages formation by the reactive oxygen species (R.O.S.). This way leads to the formation of oxidative DNA damages. In 1990, works have suggested an indirect way of DNA damages formation, the lipids peroxidation. Instead of oxidizing directly DNA, the R.O.S. oxide the lipids present in the cells and their membranes; The products coming from this degradation are able to provoke DNA damages. This way has not been studied very much. The work of this thesis is axed on this DNA theme and lipids peroxidation. In the first chapter, we begin by presenting DNA and the direct way of oxidative damages formation by the R.O.S.Then, we speak about the cell lipids suffering oxidation reactions and the different ways of lipids oxidation. Then, we present how the lipid peroxidation is a source of damages for DNA. (N.C.)

  20. Lipid corralling and poloxamer squeeze-out in membranes

    DEFF Research Database (Denmark)

    Wu, G.H.; Majewski, J.; Ege, C.

    2004-01-01

    Using x-ray scattering measurements we have quantitatively determined the effect of poloxamer 188 (P188), a polymer known to seal damaged membranes, on the structure of lipid monolayers. P188 selectively inserts into low lipid-density regions of the membrane and "corrals" lipid molecules to pack...... tightly, leading to unexpected Bragg peaks at low nominal lipid density and inducing lipid/poloxamer phase separation. At tighter lipid packing, the once inserted P188 is squeezed out, allowing the poloxamer to gracefully exit when the membrane integrity is restored....

  1. Interaction of antimicrobial peptides with lipid membranes

    Energy Technology Data Exchange (ETDEWEB)

    Hanulova, Maria

    2008-12-15

    This study aims to investigate the difference in the interaction of antimicrobial peptides with two classes of zwitterionic peptides, phosphatidylethanolamines (PE) and phosphatidylcholines (PC). Further experiments were performed on model membranes prepared from specific bacterial lipids, lipopolysaccharides (LPS) isolated from Salmonella minnesota. The structure of the lipid-peptide aqueous dispersions was studied by small-and wide-angle X-ray diffraction during heating and cooling from 5 to 85 C. The lipids and peptides were mixed at lipid-to-peptide ratios 10-10000 (POPE and POPC) or 2-50 (LPS). All experiments were performed at synchrotron soft condensed matter beamline A2 in Hasylab at Desy in Hamburg, Germany. The phases were identified and the lattice parameters were calculated. Alamethicin and melittin interact in similar ways with the lipids. Pure POPC forms only lamellar phases. POPE forms lamellar phases at low temperatures that upon heating transform into a highly curved inverse hexagonal phase. Insertion of the peptide induced inverse bicontinuous cubic phases which are an ideal compromise between the curvature stress and the packing frustration. Melittin usually induced a mixture of two cubic phases, Im3m and Pn3m, with a ratio of lattice parameters close to 1.279, related to the underlying minimal surfaces. They formed during the lamellar to hexagonal phase transition and persisted during cooling till the onset of the gel phase. The phases formed at different lipid-to-peptide ratios had very similar lattice parameters. Epitaxial relationships existed between coexisting cubic phases and hexagonal or lamellar phases due to confinement of all phases to an onion vesicle, a vesicle with several layers consisting of different lipid phases. Alamethicin induced the same cubic phases, although their formation and lattice parameters were dependent on the peptide concentration. The cubic phases formed during heating from the lamellar phase and their onset

  2. Interaction of antimicrobial peptides with lipid membranes

    International Nuclear Information System (INIS)

    Hanulova, Maria

    2008-12-01

    This study aims to investigate the difference in the interaction of antimicrobial peptides with two classes of zwitterionic peptides, phosphatidylethanolamines (PE) and phosphatidylcholines (PC). Further experiments were performed on model membranes prepared from specific bacterial lipids, lipopolysaccharides (LPS) isolated from Salmonella minnesota. The structure of the lipid-peptide aqueous dispersions was studied by small-and wide-angle X-ray diffraction during heating and cooling from 5 to 85 C. The lipids and peptides were mixed at lipid-to-peptide ratios 10-10000 (POPE and POPC) or 2-50 (LPS). All experiments were performed at synchrotron soft condensed matter beamline A2 in Hasylab at Desy in Hamburg, Germany. The phases were identified and the lattice parameters were calculated. Alamethicin and melittin interact in similar ways with the lipids. Pure POPC forms only lamellar phases. POPE forms lamellar phases at low temperatures that upon heating transform into a highly curved inverse hexagonal phase. Insertion of the peptide induced inverse bicontinuous cubic phases which are an ideal compromise between the curvature stress and the packing frustration. Melittin usually induced a mixture of two cubic phases, Im3m and Pn3m, with a ratio of lattice parameters close to 1.279, related to the underlying minimal surfaces. They formed during the lamellar to hexagonal phase transition and persisted during cooling till the onset of the gel phase. The phases formed at different lipid-to-peptide ratios had very similar lattice parameters. Epitaxial relationships existed between coexisting cubic phases and hexagonal or lamellar phases due to confinement of all phases to an onion vesicle, a vesicle with several layers consisting of different lipid phases. Alamethicin induced the same cubic phases, although their formation and lattice parameters were dependent on the peptide concentration. The cubic phases formed during heating from the lamellar phase and their onset

  3. Membrane Lipid Oscillation: An Emerging System of Molecular Dynamics in the Plant Membrane.

    Science.gov (United States)

    Nakamura, Yuki

    2018-03-01

    Biological rhythm represents a major biological process of living organisms. However, rhythmic oscillation of membrane lipid content is poorly described in plants. The development of lipidomic technology has led to the illustration of precise molecular profiles of membrane lipids under various growth conditions. Compared with conventional lipid signaling, which produces unpredictable lipid changes in response to ever-changing environmental conditions, lipid oscillation generates a fairly predictable lipid profile, adding a new layer of biological function to the membrane system and possible cross-talk with the other chronobiological processes. This mini review covers recent studies elucidating membrane lipid oscillation in plants.

  4. Paracetamol, 3-monoalkyl- and 3,5-dialkyl-substituted derivatives. Antioxidant activity and relationship between lipid peroxidation and cytotoxicity

    NARCIS (Netherlands)

    Van de Straat, R; Bijloo, G.J.; Vermeulen, N P

    1988-01-01

    The analgesic drug paracetamol is known to cause lipid peroxidation and hepatotoxicity after overdosage. In this paper, the relationship between lipid peroxidation and toxicity in freshly isolated hepatocytes was studied using paracetamol and three 3-monoalkyl-substituted derivatives of paracetamol.

  5. Effects of dietary alpha-tocopherol and beta-carotene on lipid peroxidation induced by methyl mercuric chloride in mice

    DEFF Research Database (Denmark)

    Andersen, H R; Andersen, O

    1993-01-01

    -Tocopherol did not protect against CH3HgCl induced lipid peroxidation in the brain. Excess dietary beta-carotene further enhanced CH3HgCl induced lipid peroxidation in liver, kidney and brain. CH3HgCl significantly decreased the activity of total glutathione peroxidase (T-GSH-Px) and Se-dependent glutathione...

  6. Role of lipid peroxidation and oxidative stress in 3-methylindole pneumotoxicity

    International Nuclear Information System (INIS)

    Cary, M.G.

    1985-01-01

    The cytochrome P-450-catalyzed metabolism of 3-methylindole (3-MI) results in acute lung injury in ruminants and horses. Experiments were conducted to determine the role of lipid peroxidation and oxidative stress in 3-MI pneumotoxicity in goats. Goats were given methylethylketone peroxide (MEKP), a potent peroxidant, 3-MI, indole, or cremophor-EL vehicle. The levels of shortchain hydrocarbons in expired air were measured for 6 hours post-dosing by gas chromatography. Exhaled hydrocarbons increased 20 to 30 fold within 1 hour in goats given MEKP. No significant changes were seen in goats given 3-Mi, indole or cremophor-EL. Levels of thiobarbituric acid-reactive substances, an indicator of lipid peroxidation, were significantly increased in lung tissue from goats given MEKP. In goats given 3-MI, indole or cremophor-EL, the levels were not significantly different from each other. Goats were killed at 6 hours post-dosing and examined post mortem. Bronchiolar epithelial necrosis was seen in goats given 3-MI but there were not lung lesions in other groups. The role of oxygen radicals in 3-MI pneumotoxicity was examined in a goat lung explant system using 51 Cr release as an indicator of cytotoxicity. The results of these studies provide no evidence to support the view that 3-MI pneumotoxicity involves lipid peroxidation or oxidative stress as a result of formation of oxygen or xenobiotic radicals

  7. Effects of alginate on frozen-thawed boar spermatozoa quality, lipid peroxidation and antioxidant enzymes activities.

    Science.gov (United States)

    Hu, Jinghua; Geng, Guoxia; Li, Qingwang; Sun, Xiuzhu; Cao, Hualin; Liu, Yawei

    2014-06-30

    Although alginate was reported to play an important role as free radical scavengers in vitro and could be used as sources of natural antioxidants, there was no study about the cryoprotective effects of alginate on boar spermatozoa freezing. The objective of this research was to evaluate the effects of different concentrations of alginate added to the freezing extenders on boar spermatozoa motility, plasma membrane integrity, acrosomal integrity, mitochondrial activities, lipid peroxidation and antioxidative enzymes activities (SOD and GSH-Px) after thawing. Alginate was added to the TCG extender to yield six different final concentrations: 0, 0.2, 0.4, 0.6, 0.8, and 1.0mg/mL. The semen extender supplemented with various doses of alginate increased (Pboar spermatozoa acrosomal integrity at concentrations of 0.6, 0.8, 1.0mg/mL, compared with that of the control (Pextenders with the presence of alginate led to higher SOD and GSH-Px activities and lower MDA levels, in comparison to the control (Pboar spermatozoa motility, functional integrity and antioxidative capacity at appropriate concentrations. Therefore alginate could be employed as an effective cryoprotectant in boar spermatozoa cryopreservation. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Exercise performance, red blood cell deformability, and lipid peroxidation: effects of fish oil and vitamin E

    NARCIS (Netherlands)

    Oostenbrug, G. S.; Mensink, R. P.; Hardeman, M. R.; de Vries, T.; Brouns, F.; Hornstra, G.

    1997-01-01

    Previous studies have indicated that fish oil supplementation increases red blood cell (RBC) deformability, which may improve exercise performance. Exercise alone, or in combination with an increase in fatty acid unsaturation, however, may enhance lipid peroxidation. Effects of a bicycle time trial

  9. The influense of herbs origin drugs on lipid peroxidization during acute toxic damage of liver

    NARCIS (Netherlands)

    Katikova, OY; Kostin, UV; Yagudina, RI; Tishcin, VC

    2001-01-01

    The influence of the original vegetable complexes (which include: juices of beet-rout and carrot, decoction of degrose berries, extracts of corn silk, leaves of peppermint and some other components) on the indicators of the cytolysis, lipid peroxidation and antioxidant system of serum of the

  10. Impact of air pollution on oxidative DNA damage and lipid peroxidation in mothers and their newborns.

    Czech Academy of Sciences Publication Activity Database

    Ambrož, Antonín; Vlková, Veronika; Rössner ml., Pavel; Rössnerová, Andrea; Švecová, Vlasta; Milcová, Alena; Pulkrabová, J.; Hajslová, J.; Velemínský Jr., M.; Solanský, Ivo; Šrám, Radim

    2016-01-01

    Roč. 219, č. 6 (2016), s. 545-556 ISSN 1438-4639 R&D Projects: GA ČR(CZ) GA13-13458S Institutional support: RVO:68378041 Keywords : air pollution * benzo[a]pyrene * lipid peroxidation Subject RIV: DN - Health Impact of the Environment Quality Impact factor: 4.643, year: 2016

  11. Lipid peroxidation, detoxification capacity, and genome damage in mice after transplacental exposure to pharmaceutical drugs

    Directory of Open Access Journals (Sweden)

    D. Markovic

    2013-12-01

    Full Text Available Data on genome damage, lipid peroxidation, and levels of glutathione peroxidase (GPX in newborns after transplacental exposure to xenobiotics are rare and insufficient for risk assessment. The aim of the current study was to analyze, in an animal model, transplacental genotoxicity, lipid peroxidation, and detoxification disturbances caused by the following drugs commonly prescribed to pregnant women: paracetamol, fluconazole, 5-nitrofurantoin, and sodium valproate. Genome damage in dams and their newborn pups transplacentally exposed to these drugs was investigated using the in vivo micronucleus (MN assay. The drugs were administered to dams intraperitoneally in three consecutive daily doses between days 12 and 14 of pregnancy. The results were correlated, with detoxification capacity of the newborn pups measured by the levels of GPX in blood and lipid peroxidation in liver measured by malondialdehyde (HPLC-MDA levels. Sodium valproate and 5-nitrofurantoin significantly increased MN frequency in pregnant dams. A significant increase in the MN frequency of newborn pups was detected for all drugs tested. This paper also provides reference levels of MDA in newborn pups, according to which all drugs tested significantly lowered MDA levels of newborn pups, while blood GPX activity dropped significantly only after exposure to paracetamol. The GPX reduction reflected systemic oxidative stress, which is known to occur with paracetamol treatment. The reduction of MDA in the liver is suggested to be an unspecific metabolic reaction to the drugs that express cytotoxic, in particular hepatotoxic, effects associated with oxidative stress and lipid peroxidation.

  12. Effect of the microfiltration process on antioxidant activity and lipid peroxidation protection capacity of blackberry juice

    Directory of Open Access Journals (Sweden)

    Gabriela Azofeifa

    2011-08-01

    Full Text Available Phytochemicals are highly concentrated in berries, especially polyphenols as anthocyanins and ellagitannins. These compounds have been associated with antioxidant capacity, lipid peroxidation protection, anti-inflammatory activity, anti-carcinogenic activity, obesity prevention and others. Blackberries are commonly grown and consumed as juice in Latin-American countries. However, blackberry juice is easily fermented and different industrial techniques are being applied to enable the juice to be stored for longer periods. One important issue required for these techniques is to preserve the health-promoting capacities of blackberries. This study compared the antioxidant activity and the lipid peroxidation protector effect between a fresh blackberry juice (FJ and a microfiltrated blackberry juice (MJ. Chemical analysis of both juices show less polyphenols concentration in the MJ. Despite this difference, values for biological activities, such as protection of lipid peroxidation, was not significantly different between FJ and MJ. These results suggest that the compounds responsible for the antioxidant activity are maintained even after microfiltration and the free radical scavenging capacity of these compounds could protect the initiation of lipid peroxidation. Microfiltration could be used as an industrial technique to produce blackberry juice that maintains biological activities of polyphenols.

  13. Effect of nickel chloride on hepatic lipid peroxidation and glutathione concentration in mice

    DEFF Research Database (Denmark)

    Andersen, H R; Andersen, O

    1989-01-01

    Intraperitoneal administration of nickel chloride enhanced hepatic lipid peroxidation (HLP) in 6-wk-old and 8-12-wk-old male CBA-mice but not in 3-wk-old mice. Nickel chloride administration depleted hepatic GSH in 8-12-wk-old mice but not in the younger age groups. After 300 mumol NiCl2/kg...

  14. FEATURES OF LIPID PEROXIDATION AND NEUROTROPHIC REGULATION IN PATIENTS SUFFERING FROM PARANOID SCHIZOPHRENIA

    Directory of Open Access Journals (Sweden)

    E.V. Kolesnichenko

    2008-09-01

    Full Text Available The article deals with the features of lipid peroxidation, activity of the antioxidative systems and level of brain-derived neurotrophic factor in patients with paranoid schizophrenia. Present study indicates associations between the studied parameters and type of progression, duration of disease and gender of patients.

  15. Membrane Contact Sites: Complex Zones for Membrane Association and Lipid Exchange

    Science.gov (United States)

    Quon, Evan; Beh, Christopher T.

    2015-01-01

    Lipid transport between membranes within cells involves vesicle and protein carriers, but as agents of nonvesicular lipid transfer, the role of membrane contact sites has received increasing attention. As zones for lipid metabolism and exchange, various membrane contact sites mediate direct associations between different organelles. In particular, membrane contact sites linking the plasma membrane (PM) and the endoplasmic reticulum (ER) represent important regulators of lipid and ion transfer. In yeast, cortical ER is stapled to the PM through membrane-tethering proteins, which establish a direct connection between the membranes. In this review, we consider passive and facilitated models for lipid transfer at PM–ER contact sites. Besides the tethering proteins, we examine the roles of an additional repertoire of lipid and protein regulators that prime and propagate PM–ER membrane association. We conclude that instead of being simple mediators of membrane association, regulatory components of membrane contact sites have complex and multilayered functions. PMID:26949334

  16. [Peroxide modification of membranes and isomorphic composition of cytochrome P-450 of rat liver microsomes during antioxidant deficiency].

    Science.gov (United States)

    Gubskiy, Iu I; Paramonova, G I; Boldeskul, A E; Primak, R G; Bogdanova, L A; Zadorina, O V; Litvinova, N V

    1992-01-01

    Lipid peroxidation (LPO), physico-chemical properties of the membranes and isoformic composition of microsomal cytochrome P-450 from the rat liver were studied under conditions of antioxidant insufficiency (AOI) which was modelled by exclusion of alpha-tocopherol from the animals' ration. An insignificant accumulation of microsomal diene conjugates and schiff bases against a sharp increase of the ability to the prooxidant stimulated LPO in vitro took place. A significant decrease of membrane lipid microviscosity and a change in surface properties of microsomal membranes of rats with AOI was determined. Absence of alpha-tocopherol in the ration was accompanied by a significant change in the content of separate isoforms of cytochrome P-450 exhibited in growth of a polypeptide with m. w. 54 kDa and the lowering of proteins with m. w. 48 and 50 kDa. Less intensive quenching of tryptophan fluorescence by acrylamide was also revealed, which testified to a lower accessibility of the quencher to membrane proteins or their fluorophore sites. Modification of lipid composition and of physicochemical properties of the rat liver membrane microsomes which was observed at AOI was significantly correlated by pretreatment with the antioxidant 4-methyl-2,6-ditretbutylphenol (ionol).

  17. Protein-lipid interactions: from membrane domains to cellular networks

    National Research Council Canada - National Science Library

    Tamm, Lukas K

    2005-01-01

    ... membranes is the lipid bilayer. Embedded in the fluid lipid bilayer are proteins of various shapes and traits. This volume illuminates from physical, chemical and biological angles the numerous - mostly quite weak - interactions between lipids, proteins, and proteins and lipids that define the delicate, highly dynamic and yet so stable fabri...

  18. Imaging of blood plasma coagulation at supported lipid membranes.

    Science.gov (United States)

    Faxälv, Lars; Hume, Jasmin; Kasemo, Bengt; Svedhem, Sofia

    2011-12-15

    The blood coagulation system relies on lipid membrane constituents to act as regulators of the coagulation process upon vascular trauma, and in particular the 2D configuration of the lipid membranes is known to efficiently catalyze enzymatic activity of blood coagulation factors. This work demonstrates a new application of a recently developed methodology to study blood coagulation at lipid membrane interfaces with the use of imaging technology. Lipid membranes with varied net charges were formed on silica supports by systematically using different combinations of lipids where neutral phosphocholine (PC) lipids were mixed with phospholipids having either positively charged ethylphosphocholine (EPC), or negatively charged phosphatidylserine (PS) headgroups. Coagulation imaging demonstrated that negatively charged SiO(2) and membrane surfaces exposing PS (obtained from liposomes containing 30% of PS) had coagulation times which were significantly shorter than those for plain PC membranes and EPC exposing membrane surfaces (obtained from liposomes containing 30% of EPC). Coagulation times decreased non-linearly with increasing negative surface charge for lipid membranes. A threshold value for shorter coagulation times was observed below a PS content of ∼6%. We conclude that the lipid membranes on solid support studied with the imaging setup as presented in this study offers a flexible and non-expensive solution for coagulation studies at biological membranes. It will be interesting to extend the present study towards examining coagulation on more complex lipid-based model systems. Copyright © 2011 Elsevier Inc. All rights reserved.

  19. Modulation of keratinocyte expression of antioxidants by 4-hydroxynonenal, a lipid peroxidation end product

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Ruijin [Pharmacology and Toxicology and Pharmaceutics, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ (United States); Heck, Diane E. [Environmental Health Science, New York Medical College, Valhalla, NY (United States); Mishin, Vladimir; Black, Adrienne T. [Pharmacology and Toxicology and Pharmaceutics, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ (United States); Shakarjian, Michael P. [Environmental Health Science, New York Medical College, Valhalla, NY (United States); Kong, Ah-Ng Tony; Laskin, Debra L. [Pharmacology and Toxicology and Pharmaceutics, Ernest Mario School of Pharmacy, Rutgers University, Piscataway, NJ (United States); Laskin, Jeffrey D., E-mail: jlaskin@eohsi.rutgers.edu [Environmental and Occupational Medicine, Rutgers University-Robert Wood Johnson Medical School, Piscataway, NJ (United States)

    2014-03-01

    4-Hydroxynonenal (4-HNE) is a lipid peroxidation end product generated in response to oxidative stress in the skin. Keratinocytes contain an array of antioxidant enzymes which protect against oxidative stress. In these studies, we characterized 4-HNE-induced changes in antioxidant expression in mouse keratinocytes. Treatment of primary mouse keratinocytes and PAM 212 keratinocytes with 4-HNE increased mRNA expression for heme oxygenase-1 (HO-1), catalase, NADPH:quinone oxidoreductase (NQO1) and glutathione S-transferase (GST) A1-2, GSTA3 and GSTA4. In both cell types, HO-1 was the most sensitive, increasing 86–98 fold within 6 h. Further characterization of the effects of 4-HNE on HO-1 demonstrated concentration- and time-dependent increases in mRNA and protein expression which were maximum after 6 h with 30 μM. 4-HNE stimulated keratinocyte Erk1/2, JNK and p38 MAP kinases, as well as PI3 kinase. Inhibition of these enzymes suppressed 4-HNE-induced HO-1 mRNA and protein expression. 4-HNE also activated Nrf2 by inducing its translocation to the nucleus. 4-HNE was markedly less effective in inducing HO-1 mRNA and protein in keratinocytes from Nrf2 −/− mice, when compared to wild type mice, indicating that Nrf2 also regulates 4-HNE-induced signaling. Western blot analysis of caveolar membrane fractions isolated by sucrose density centrifugation demonstrated that 4-HNE-induced HO-1 is localized in keratinocyte caveolae. Treatment of the cells with methyl-β-cyclodextrin, which disrupts caveolar structure, suppressed 4-HNE-induced HO-1. These findings indicate that 4-HNE modulates expression of antioxidant enzymes in keratinocytes, and that this can occur by different mechanisms. Changes in expression of keratinocyte antioxidants may be important in protecting the skin from oxidative stress. - Highlights: • Lipid peroxidation generates 4-hydroxynonenal, a reactive aldehyde. • 4-HNE induces antioxidant proteins in mouse keratinocytes. • Induction of

  20. The effects of 1800 MHz radiofrequency waves on lipid peroxidation in pregnant rabbits

    International Nuclear Information System (INIS)

    Tomruk, Arin; Guler, Goknur; Seyhan, Nesrin

    2008-01-01

    Full text: The radiofrequency (RF) part of the Electromagnetic (EM) spectrum includes EM waves used mainly for telecommunications purposes (Radio and TV broadcasting, wireless phones, pagers, cordless phones, police and fire department radios, point-to-point links and satellite communications all rely on RF energy) and also used in some industrial technologies (industrial heaters and sealers), medical treatments (Diathermy units), microwave ovens and radar technologies. With rapid advances in these technologies, exposure to RF radiation of people has also increased. Some biological effects have been associated with exposure to RF and it is well established that RF exposures may lead to changes in cell membrane functions, cell metabolism. Changes in cell membrane functions include chemical reactions occurred between main membrane components (phospholipids, cholesterol, etc) and oxidative stress products such as Reactive Oxygen Species (ROS) and Reactive Nitrogen Species (RNS). Oxidative attacks of ROS and RNS can cause degradation of these unsaturated lipids and this degradation can be referred as lipid peroxidation (LPO). Malondialdehyde (MDA) is the end product of the major chain reactions leading to oxidation of polyunsaturated fatty acids and serves as a reliable marker of oxidative stress mediated LPO. Membrane LPO may initialize many forms of oxygen toxicity at molecular level including structural derangement of the bilayer and altered fluidity, increased permeability of cytosolic constituents, inactivation of intrinsic enzymes and transporters, covalent cross-linking of lipids and proteins, polypeptide strand scission and DNA damage and mutagenesis. In the present study, the investigation of the possible RF radiation's effects on LPO was aimed particularly. A total forty New Zeland White rabbits (weighted 3-5 kg, 16 months) were randomly divided into four groups which are composed of 10 rabbits each for groups. 1) Group I (sham, non-pregnant group); 2) Group

  1. The lipid organisation of the cell membrane

    Directory of Open Access Journals (Sweden)

    Ladha, S.

    2000-04-01

    Full Text Available Lipids and proteins in biological membranes are arranged in a mosaic of domains in the membrane. These domains represent small-scale heterogeneities in composition, shape and fluidity within the plane of the membrane, over the range of hundreds of nanometers to a few micrometers. They arise from the complex interactions of the heterogeneous mixtures of phospholipids, sterols, and proteins that make up all biological membranes.Los lípidos y las proteínas en las membranas biológicas están dispuestos en un mosaico de campos en la membrana. Estos campos representan heterogeneidades a pequeña escala en la composición, forma y fluidez dentro del plano de la membrana, en un rango que va de los cientos de nanómetros a los pocos micrómetros. Estos campos se originan de las complejas interacciones de las mezclas heterogéneas de fosfolípidos, esteroles y proteínas de las que están hechas todas y cada una de las membranas biológicas.

  2. Inhibition of rat microsomal lipid peroxidation by the oral administration of D002

    Directory of Open Access Journals (Sweden)

    Menéndez R.

    2000-01-01

    Full Text Available The effect of D002, a defined mixture of higher primary alcohols purified from bee wax, on in vivo and in vitro lipid peroxidation was studied. The extent of lipid peroxidation was measured on the basis of the levels of thiobarbituric acid reactive substances (TBARS. When D002 (5-100 mg/kg body weight was administered orally to rats for two weeks, a partial inhibition of the in vitro enzymatic and non-enzymatic lipid peroxidation was observed in liver and brain microsomes. Maximal protection (46% occurred at a dose of 25 mg/kg. D002 behaved differently depending on both the presence of NADPH and the integrity of liver microsomes, which suggests that under conditions where microsomal metabolism was favored the protective effect of D002 was increased. D002 (25 mg/kg also completely inhibited carbon tetrachloride- and toluene-induced in vivo lipid peroxidation in liver and brain. Also, D002 significantly lowered in a dose-dependent manner the basal level of TBARS in liver (19-40% and brain (28-44% microsomes. We conclude that the oral administration of D002 (5, 25 and 100 mg/kg for two weeks protected rat liver and brain microsomes against microsomal lipid peroxidation in vitro and in vivo. Thus, D002 could be useful as a dietary natural antioxidant supplement. More studies are required before these data can be extrapolated to the recommendation for the use of D002 as a dietary antioxidant supplement for humans.

  3. Effect of Cryphonectria parasitica toxin on lipid peroxidation and ...

    African Journals Online (AJOL)

    Jane

    2011-10-24

    Oct 24, 2011 ... African Journal of Biotechnology Vol. 10(65) ... on membrane systems of the cells were lighter and they occurred later than expected in the resistant ..... Starch was accumulated normally in chloroplasts after Cp-toxin treatment and the starch inclusions continued to enlarge in all stages of treated leaves cells ...

  4. Protective effect of morin on lipid peroxidation and lipid profile in ammonium chloride-induced hyperammonemic rats

    OpenAIRE

    S Subash; P Subramanian

    2012-01-01

    Objective: To evaluated the protective effects of morin (3, 5, 7, 2', 4'-pentahydroxyflavone) on lipid peroxidation and lipid levels during ammonium chloride (AC) induced hyperammonemia in experimental rats. Methods: Thirty two male albino Wistar rats, which are weighing between 180-200 g were used for the study. The hyperammonemia was induced by administration of 100 mg/kg body weight (i.p. ) thrice in a week of AC for 8 weeks. Rats were treated with morin at dose (30 mg/kg bo...

  5. Lipidomics in research on yeast membrane lipid homeostasis.

    Science.gov (United States)

    de Kroon, Anton I P M

    2017-08-01

    Mass spectrometry is increasingly used in research on membrane lipid homeostasis, both in analyses of the steady state lipidome at the level of molecular lipid species, and in pulse-chase approaches employing stable isotope-labeled lipid precursors addressing the dynamics of lipid metabolism. Here my experience with, and view on mass spectrometry-based lipid analysis is presented, with emphasis on aspects of quantification of membrane lipid composition of the yeast Saccharomyces cerevisiae. This article is part of a Special Issue entitled: BBALIP_Lipidomics Opinion Articles edited by Sepp Kohlwein. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. The lipid peroxidation intensity of fungi strains from the orders Agaricales and Polyporales

    Directory of Open Access Journals (Sweden)

    O. V. Fedotov

    2016-07-01

    Full Text Available This article is devoted to investigation of the dynamics of growth and level of spontaneous and induced lipid peroxidation intensity of Basidiomycetes strains grown by surface cultivation on a glucose-peptone medium. The materials of the research are mycelium and culture filtrates (CF of 57 strains (5 belong to 5 species from the order Polyporales s.l., and 52 belong to 7 species of the order Agaricales s.l.. To study the dynamics of growth we used a weighing method for determining the accumulation of absolutely dry biomass. Intensity of lipid peroxidation was determined by a modified spectrophotometric method for content of active to thiobarbituric acid products. It was found that the most productive in absolutely dry biomass accumulation were the strains Flammulina velutipes (Curt.: Fr. Sing. F-610 and Pleurotus eryngii (DC.: Fr. Quél. P-er. The level of spontaneous and induced LPO intensity in mycelia of all strains was higher than this figure in the culture filtrate and increased with the duration of cultivation. Dependencies between the content of lipid peroxidation products in the mycelia and CF were not established. The lowest values were recorded for biomass accumulation by the strains Pleurotus ostreatus (Jacq.: Fr. P. Kumm. P-14, P-192 and P. citrinopileatus Singer. Р-сіtr. Groups of basidiomycete cultures with different levels of TBA-AP were identified. Spontaneous and induced intensivity of lipid peroxidation in all studied strains of mycelia was higher than the figure in the culture filtrate. The intensity of lipid peroxidation in both mycelia and culture filtrate constantly increased, which can be explained by the growing shortage of certain nutrients (primarily carbon and increased concentration of metabolic products in the medium. The ratio of spontaneous and induced lipid peroxidation intensity is specific to each strain and is independent of its systematic position. Shifting of prooxidant-antioxidant balance to a

  7. Exposure to Anacardiaceae volatile oils and their constituents induces lipid peroxidation within food-borne bacteria cells.

    Science.gov (United States)

    Montanari, Ricardo M; Barbosa, Luiz C A; Demuner, Antonio J; Silva, Cleber J; Andrade, Nelio J; Ismail, Fyaz M D; Barbosa, Maria C A

    2012-08-14

    The chemical composition of the volatile oils from five Anacardiaceae species and their activities against Gram positive and negative bacteria were assessed. The peroxidative damage within bacterial cell membranes was determined through the breakdown product malondialdehyde (MDA). The major constituents in Anacardium humile leaves oil were (E)-caryophyllene (31.0%) and α-pinene (22.0%), and in Anacardium occidentale oil they were (E)-caryophyllene (15.4%) and germacrene-D (11.5%). Volatile oil from Astronium fraxinifolium leaves were dominated by (E)-β-ocimene (44.1%) and α-terpinolene (15.2%), whilst the oil from Myracrodruon urundeuva contained an abundance of δ-3-carene (78.8%). However, Schinus terebinthifolius leaves oil collected in March and July presented different chemical compositions. The oils from all species, except the one from A. occidentale, exhibited varying levels of antibacterial activity against Staphylococcus aureus, Bacillus cereus and Escherichia coli. Oil extracted in July from S. terebinthifolius was more active against all bacterial strains than the corresponding oil extracted in March. The high antibacterial activity of the M. urundeuva oil could be ascribed to its high δ-3-carene content. The amounts of MDA generated within bacterial cells indicate that the volatile oils induce lipid peroxidation. The results suggest that one putative mechanism of antibacterial action of these volatile oils is pro-oxidant damage within bacterial cell membrane explaining in part their preservative properties.

  8. Accumulation of lipid peroxidation products in eye structures of mice subjected to whole-body X-irradiation

    International Nuclear Information System (INIS)

    Sakina, N.L.; Dontsov, A.E.; Afanas'ev, G.G.; Ostrovskij, M.A.; Pelevina, I.I.

    1990-01-01

    In studying the effect of whole-body X-irradiation on the accumulation of lipid peroxidation products (conjugated dienes, TBA-active products, and Sciff bases) in retina and retinal pigmented epithelium of pigmented and nonpigmented mice it was shown that irradiation of dark-pigmented mice does not cause even a slight accumulation of lipid peroxidation products as compared to that in the controls. Albino mice exhibited a marked increase in the level of lipid peroxidation products which was manifested soon after irradiation and persisted for at least 3 months after irradiation. Melanine is suggested to participate in protecting eye structures against pro-oxidizing action of ionizing radiation

  9. [Correction of lipid peroxidation and antioxidant system disorders by bioflavonoids during modeling of cholesterol atherosclerosis in rabbits].

    Science.gov (United States)

    Shysh, A M; Pashevin, D O; Dosenko, V Ie; Moĭbenko, O O

    2011-01-01

    We have studied the influence of bioflavonoids (quercetin, corvitin) on lipid peroxidation and antioxidant enzymes in the modeling of cholesterol atherosclerosis in rabbits. It has been shown that simultaneous administration of the quercetin derivative corvitin suppressed lipid peroxidation. We showed that under hypercholesterolemia, the concentration of malone dialdehyde in myocardial tissue in rabbits is significantly increased, while administration of bioflavonoids decreased the concentration of malone dialdehyde by 38.3%. Furthermore, corvitin caused activating effects on antioxidant enzymes superoxide dismutase and catalase in cardiac tissue. Our data suggest that bioflavonoids are able to suppress lipid peroxidation and prevent the decrease ofantioxidant enzymes activity in rabbits with cholesterol-rich diet induced atherosclerosis.

  10. Linearly concatenated cyclobutane (ladderane) lipids form a dense bacterial membrane

    NARCIS (Netherlands)

    Sinninghe Damsté, J.S.; Strous, M.; Rijpstra, W.I.C.; Hopmans, E.C.; Geenevasen, J.A.J.; Duin, A.C.T. van; Niftrik, L.A.; Jetten, M.S.M.

    2002-01-01

    Lipid membranes are essential to the functioning of cells, enabling the existence of concentration gradients of ions and metabolites. Microbial membrane lipids can contain three-, five-, six- and even seven-membered aliphatic rings, but four-membered aliphatic cyclobutane rings have never been

  11. Tyrosine-lipid peroxide adducts from radical termination: para coupling and intramolecular Diels-Alder cyclization.

    Science.gov (United States)

    Shchepin, Roman; Möller, Matias N; Kim, Hye-young H; Hatch, Duane M; Bartesaghi, Silvina; Kalyanaraman, Balaraman; Radi, Rafael; Porter, Ned A

    2010-12-15

    Free radical co-oxidation of polyunsaturated lipids with tyrosine or phenolic analogues of tyrosine gave rise to lipid peroxide-tyrosine (phenol) adducts in both aqueous micellar and organic solutions. The novel adducts were isolated and characterized by 1D and 2D NMR spectroscopy as well as by mass spectrometry (MS). The spectral data suggest that the polyunsaturated lipid peroxyl radicals give stable peroxide coupling products exclusively at the para position of the tyrosyl (phenoxy) radicals. These adducts have characteristic (13)C chemical shifts at 185 ppm due to the cross-conjugated carbonyl of the phenol-derived cyclohexadienone. The primary peroxide adducts subsequently undergo intramolecular Diels-Alder (IMDA) cyclization, affording a number of diastereomeric tricyclic adducts that have characteristic carbonyl (13)C chemical shifts at ~198 ppm. All of the NMR HMBC and HSQC correlations support the structure assignments of the primary and Diels-Alder adducts, as does MS collision-induced dissociation data. Kinetic rate constants and activation parameters for the IMDA reaction were determined, and the primary adducts were reduced with cuprous ion to give a phenol-derived 4-hydroxycyclohexa-2,5-dienone. No products from adduction of peroxyls at the phenolic ortho position were found in either the primary or cuprous reduction product mixtures. These studies provide a framework for understanding the nature of lipid-protein adducts formed by peroxyl-tyrosyl radical-radical termination processes. Coupling of lipid peroxyl radicals with tyrosyl radicals leads to cyclohexenone and cyclohexadienone adducts, which are of interest in and of themselves since, as electrophiles, they are likely targets for protein nucleophiles. One consequence of lipid peroxyl reactions with tyrosyls may therefore be protein-protein cross-links via interprotein Michael adducts.

  12. Role of Lipid Peroxidation-Derived α, β-Unsaturated Aldehydes in Vascular Dysfunction

    Directory of Open Access Journals (Sweden)

    Seung Eun Lee

    2013-01-01

    Full Text Available Vascular diseases are the most prominent cause of death, and inflammation and vascular dysfunction are key initiators of the pathophysiology of vascular disease. Lipid peroxidation products, such as acrolein and other α, β-unsaturated aldehydes, have been implicated as mediators of inflammation and vascular dysfunction. α, β-Unsaturated aldehydes are toxic because of their high reactivity with nucleophiles and their ability to form protein and DNA adducts without prior metabolic activation. This strong reactivity leads to electrophilic stress that disrupts normal cellular function. Furthermore, α, β-unsaturated aldehydes are reported to cause endothelial dysfunction by induction of oxidative stress, redox-sensitive mechanisms, and inflammatory changes such as induction of cyclooxygenase-2 and cytokines. This review provides an overview of the effects of lipid peroxidation products, α, β-unsaturated aldehydes, on inflammation and vascular dysfunction.

  13. Influence of the Siberian larch extract on the processes of peroxide oxidation of lipids in experiment

    Directory of Open Access Journals (Sweden)

    Pateyuk Andrey

    2016-03-01

    Full Text Available In modern conditions wood processing is one of the primary branches of production in Transbaikal region. In connection with big squares of logging the question of processing and utilizing waste products directly on the spot is particularly acute. We researched the activity of water extract from sawdust of Siberian larch "Ekstrapinus" on the power exchange and processes of peroxide oxidation of lipids against immobilized stress in experiment. The data provided in the article prove that the use of Ekstrapinus extract reduces the pathological violations arising under stress. So, Ekstrapinus extract restores energy potential of cages when modeling stress, restores energy potential of cells, normalizes balance in the system "peroxide oxidation of lipids – antioxidant protection" and supports the balance of tiol in an animal organism in the state of stress. Considering absence of toxicity in the recommended doses, it is possible to recommend their application under stress.

  14. Lipid peroxidation and seed emergency in progenies of the yellow passion fruit plant

    Directory of Open Access Journals (Sweden)

    João Paulo Bestete de Oliveira

    2012-09-01

    Full Text Available The objective was to evaluate the percentage of emergency plantlets and lipid peroxidation in seeds of 29 half-sib progenies of yellow passion fruit (Passiflora edulis Sims. after 24 months under storage. The experimental design was completely randomized, with four replications of 50 seeds each, from which the treatments were the progenies (1-29. The evaluation of the percent plantlet emergency was accomplished at 14 and 28 days after sowing. The lipid peroxidation of the seeds was expressed as malondialdehyde (MDA content that was determined by the TBARS method. Approximately 21% of those half-sib progenies maintained the viability of their seeds for twenty-four months under storage. The results point out a remarkable genetic variability for vigor and emergency of the yellow passion fruit plantlets, with occurrence of individuals with high and other ones with low capacity to maintaining the physiologic quality of their seeds after storage.

  15. Lipids and Protein Peroxidation in Children and Teenager Patients with Pulmonary Tuberculosis

    Directory of Open Access Journals (Sweden)

    Yu.V. Poliakova

    2015-09-01

    Full Text Available A review of literature about the study of lipid and protein peroxidation in children and teenagers with pulmonary tuberculosis nowadays was carried out. It was established that there is a great number works dedicated to the lipid peroxidation and antioxidant protective system in various pathological conditions of the respiratory system, including pulmonary tuberculosis in children and teenagers today. Oxidative modification proteins products are the earliest markers of oxidative stress in patients. There is no information on the oxidative modification of proteins in children and teenagers suffering from pulmonary tuberculosis in the literature. The study of oxidative modification of proteins will facilitate the development of more efficient new diagnosis methods and pathogenetic treatment of children and teenagers with pulmonary tuberculosis, that will increase the treatment effectiveness.

  16. An in vitro model to test relative antioxidant potential: Ultraviolet-induced lipid peroxidation in liposomes

    International Nuclear Information System (INIS)

    Pelle, E.; Maes, D.; Padulo, G.A.; Kim, E.K.; Smith, W.P.

    1990-01-01

    Since antioxidants have been shown to play a major role in preventing some of the effects of aging and photoaging in skin, it is important to study this phenomenon in a controlled manner. This was accomplished by developing a simple and reliable in vitro technique to assay antioxidant efficacy. Inhibition of peroxidation by antioxidants was used as a measure of relative antioxidant potential. Liposomes, high in polyunsaturated fatty acids (PUFA), were dispersed in buffer and irradiated with ultraviolet (UV) light. Irradiated liposomes exhibited a significantly higher amount of hydroperoxides than liposomes containing antioxidants in a dose- and concentration-dependent manner. Lipid peroxidation was determined spectrophotometrically by an increase in thiobarbituric acid reacting substances. To further substantiate the production of lipid peroxides, gas chromatography was used to measure a decrease in PUFA substrate. In order of decreasing antioxidant effectiveness, the following results were found among lipophilic antioxidants: BHA greater than catechin greater than BHT greater than alpha-tocopherol greater than chlorogenic acid. Among hydrophilic antioxidants, ascorbic acid and dithiothreitol were effective while glutathione was ineffective. In addition, ascorbic acid was observed to act synergistically with alpha-tocopherol, which is in agreement with other published reports on the interaction of these two antioxidants. Although peroxyl radical scavengers seem to be at a selective advantage in this liposomal/UV system, these results demonstrate the validity of this technique as an assay for measuring an antioxidant's potential to inhibit UV-induced peroxidation

  17. LIPID PEROXIDATION AND BIOCHEMICAL PROFILE IN PRE AND POST ELECTROCONVULSIVE THERAPY IN PSYCHIATRIC PATIENTS

    OpenAIRE

    Narasimha Rao Babji; Santhisree

    2014-01-01

    OBJECTIVE: Electroconvulsive therapy (ECT) is an important treatment for a variety of neuropsychiatric disorders. The invasiveness of the procedure and major adverse effects of memory loss and confusion are limiting variables in the use of ECT. Free radical molecules are released during a shock seizure. The effect of electroconvulsive therapy on lipid peroxidation and on enzymes is not well studied. In the present study Malondialdehyde (MDA), Aspartate transaminase (AST), Alan...

  18. Hypoxia-induced lipid peroxidation in rat brain and protective effect of carnitine and phosphocreatine

    Czech Academy of Sciences Publication Activity Database

    Rauchová, Hana; Koudelová, J.; Drahota, Zdeněk; Mourek, J.

    2002-01-01

    Roč. 27, č. 9 (2002), s. 899-904 ISSN 0364-3190 R&D Projects: GA MŠk LN00A069 Grant - others:GA UK(XC) 22/2001 Institutional research plan: CEZ:AV0Z5011922 Keywords : hypobaric hypoxia-lipid peroxidation * carnitine * lactate/pyruvate ratio Subject RIV: ED - Physiology Impact factor: 1.672, year: 2002

  19. The effects of therapeutic concentrations ofamisulpride andrisperidone on human plasma lipid peroxidation – invitro studies

    Directory of Open Access Journals (Sweden)

    Anna Dietrich-Muszalska

    2011-09-01

    Full Text Available Introduction: Antipsychotics may in different ways affect the oxidative stress measured by plasma lipid peroxidation. Probably some of them may intensify the oxidative balance disturbances occurring in schizophrenia. The effects of amisulpride and risperidone on redox processes are not known sufficiently yet. Aim of the study: Establishment of the effects of amisulpride and risperidone on human plasma lipid peroxidation measured by determination of the level of thiobarbituric acid-reactive substances (TBARS, in vitro. Material and methods: Blood for the studies was collected from healthy volunteers (aged 24-26 years for ACD solution. Active substances of the examined drugs were dissolved in 0.01% dimethylsulfoxide (DMSO to the final concentrations (of amisulpride 578 ng/ml and risperidone 64 ng/ml and incubated with plasma for 1 and 24 hours at 37ºC. For each experiment the control samples of plasma with DMSO (without the drug were performed. The lipid peroxidation level was measured in plasma by determining the TBARS concentration, using the spectrophotometric method (acc. to Rice-Evans, 1991. The results were analysed using the following statistical methods: the paired Student t-test and ANOVA II variance analysis and NIR test (StatSoft Inc., Statistica v. 6.0. Results: The ANOVA II variance analysis indicated significant differences in the effects of both drugs on TBARS level (F=4.26; df=2, p0.05. Conclusion: Amisulpride and risperidone in concentrations corresponding to doses recommended for treatment of acute episode of schizophrenia do not induce oxidative stress measured by lipid peroxidation. Unlike risperidone, amisulpride exhibits antioxidative effects.

  20. The Protective Effect of Hippophae Rhamnoides Carotenoid Extract Against Lipid Peroxidation in Crude Vegetable Oils

    Directory of Open Access Journals (Sweden)

    Sanda Andrei

    2014-11-01

    Full Text Available Vegetable oils are important elements of the human diet because they contain essential nutritional factors. Due to the manufacturing processes or inadequate conditions of storage, they may also contain lipid oxidation products that are toxic to the body. The purpose of this paper is to test the protective effect of carotenoid-rich extracts obtained from the fruits of Hippophae rhamnoides on crude sunflower, pumpkin and olive oils oxidative processes. In order to evaluate the effect of antioxidant carotenoids, three stages were followed: thermal induction of lipid peroxidation in the presence of AAPH (2,2'-Azobis(2-amidinopropane dihydrochloride; determination of the level of lipid peroxidation in oxidized oils in the presence and absence of antioxidants, by quantifying the concentration of conjugated dienes and malonyl dialdehyde (MDA; determination of the level of lipid peroxidation by evaluating the profile of the fatty acids and the ratio between the saturated and unsaturated fatty acids (UFA / SFA, using an GC-MS method. In the case of sunflower oil, it was observed that sea buckthorn fruit extract significantly decreased MDA concentration but does not significantly reduce the concentration of conjugated dienes. The protective effect of carotenoids is more evident in the case of oil from pumpkin seeds. In the olive oil, unlike the first two types of oils, the carotenoids extract inhibits both the MDA and the conjugated dienes formation to a lesser extent, statistically insignificant. Overall, the ratio UFA / SFA decreases in crude oxidized oils. In the oils in which carotenoids were added was observed an increase in the UFA / SFA ratio. Carotenoids fraction from sea buckthorn fruits, rich in xanthophylls’ esters, possess a good antioxidant effect, protecting vegetable oils against peroxidation processes induced in the presence of AAPH

  1. Homeoviscous adaptation and the regulation of membrane lipids

    DEFF Research Database (Denmark)

    Ernst, Robert; Ejsing, Christer S; Antonny, Bruno

    2016-01-01

    Biological membranes are complex and dynamic assemblies of lipids and proteins. Poikilothermic organisms including bacteria, fungi, reptiles, and fish do not control their body temperature and must adapt their membrane lipid composition in order to maintain membrane fluidity in the cold. This ada......Biological membranes are complex and dynamic assemblies of lipids and proteins. Poikilothermic organisms including bacteria, fungi, reptiles, and fish do not control their body temperature and must adapt their membrane lipid composition in order to maintain membrane fluidity in the cold....... This adaptive response was termed homeoviscous adaptation and has been frequently studied with a specific focus on the acyl chain composition of membrane lipids. Massspectrometry-based lipidomics can nowadays provide more comprehensive insights into the complexity of lipid remodeling during adaptive responses...... such as neurons maintain unique lipid compositions with specific physicochemical properties. To date little is known about the sensory mechanisms regulating the acyl chain profile in such specialized cells or during adaptive responses. Here we summarize our current understanding of lipid metabolic networks...

  2. Blood antioxidant profile and lipid peroxides in dairy cows with clinical mastitis

    Directory of Open Access Journals (Sweden)

    Rajesh Rathore

    2013-10-01

    Full Text Available Aim: To evaluate blood antioxidant profile and lipid peroxides in dairy cows with clinical mastitis. Materials and Methods: Twelve cases of clinical mastitis in cross-bred cows were selected based on physical examination of udder and milk, California Mastitis Test (CMT, Somatic Cell Count (SCC and confirmation by bacteriological examination of milk and requisite biochemical tests. Twelve lactating cows showing negative CMT reaction and SCC <2x105 cells/ml were considered as healthy control. Antioxidant parameters measured in blood were superoxide dismutase (SOD, catalase activities and reduced glutathione (GSH concentration. Erythrocytic lipid peroxidation (LPO was measured in terms of malondialdehyde (MDA production. Results: Significant (P<0.05 decrease in blood SOD and catalase activities, GSH concentration and an increase in erythrocytic lipid peroxides was observed in cows with clinical mastitis. Conclusion: It is concluded that there is a compromise in antioxidant defense of the body in dairy cows with clinical mastitis resulting in oxidative damage, therefore, necessitate the use of antioxidants and other protective compounds along with conventional therapy for mastitis control. [Vet World 2013; 6(5.000: 271-273

  3. Influence of Curcumin on the Redox System and Lipid Peroxidation in Gamma Irradiated Rats

    International Nuclear Information System (INIS)

    Zahran, A.M.

    2007-01-01

    Naturally occurring micro nutrients polyphenolic compounds have received increased attention in the maintenance of health. Curcumin, the main active biological phyto chemical constituents of Turmeric (Curcuma longa L. rhizomes), is known for its wide range of medicinal properties. The present study was designed to evaluate the potential efficacy of curcumin administration against redox imbalance state and cytotoxic induced by protracted exposure to 'y-rays. Curcumin was orally administered to Sprague Dawley male albino rats simultaneously via intragastric intubation (80 mg/ Kg body wt) for 7 days before exposure to gamma- rays and continued during the whole period of irradiation processing. Whole body γ-rays was delivered as fractionated doses (3 weeks) 3 Gy increment every week up to total cumulative dose of (9 Gy). The results obtained showed increased level of lipid peroxides contents and xanthine oxidase (XO) activity in irradiated animal groups with concomitant depletion in the level of reduced glutathione (GSH) and activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GSFI-Px). Administration of curcumin has significantly lowered the level of lipid peroxidation and enhanced the antioxidant status of irradiated animals. It could he concluded that curcumin exerts a protective effect against radiation-induced cytotoxic by modulating the extent of lipid peroxidation and augmenting antioxidant defence system

  4. Novel free-radical mediated lipid peroxidation biomarkers in newborn plasma.

    Science.gov (United States)

    Sánchez-Illana, Ángel; Thayyil, Sudhin; Montaldo, Paolo; Jenkins, Dorothea; Quintás, Guillermo; Oger, Camille; Galano, Jean-Marie; Vigor, Claire; Durand, Thierry; Vento, Máximo; Kuligowski, Julia

    2017-12-15

    Oxidative stress derived from perinatal asphyxia appears to be closely linked to neonatal brain damage and lipid peroxidation biomarkers have shown to provide predictive power of oxidative stress related pathologies in situations of hypoxia and reoxygenation in the newborn. The objective of this work was to develop and validate of a comprehensive liquid chromatography tandem mass spectrometry approach for the quantitative profiling of 28 isoprostanoids in newborn plasma samples covering a broad range of lipid peroxidation product classes. The method was developed taking into account the specific requirements for its use in neonatology (i.e. limited sample volumes, straightforward sample processing and high analytical throughput). The method was validated following stringent FDA guidelines and was then applied to the analysis of 150 plasma samples collected from newborns. Information obtained from the quantitative analysis of isoprostanoids was critically compared to that provided by a previously developed approach aiming at the semi-quantitative detection of total parameters of fatty acid derived lipid peroxidation biomarkers. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Mitochondria as a source and target of lipid peroxidation products in healthy and diseased heart.

    Science.gov (United States)

    Anderson, Ethan J; Katunga, Lalage A; Willis, Monte S

    2012-02-01

    The heart is a highly oxidative organ in which cardiomyocyte turnover is virtually absent, making it particularly vulnerable to accumulation of lipid peroxidation products (LPP) formed as a result of oxidative damage. Reactive oxygen and nitrogen species are the most common electrophiles formed during lipid peroxidation and lead to the formation of both stable and unstable LPP. Of the LPP formed, highly reactive aldehydes are a well-recognized causative factor in ageing and age-associated diseases, including cardiovascular disease and diabetes. Recent studies have identified that the mitochondria are both a primary source and target of LPP, with specific emphasis on aldehydes in cardiomyocytes and how these affect the electron transport system and Ca(2+) balance. Numerous studies have found that there are functional consequences in the heart following exposure to specific aldehydes (acrolein, trans-2-hexanal, 4-hydroxynonenal and acetaldehyde). Because these LPP are known to form in heart failure, cardiac ischaemia-reperfusion injury and diabetes, they may have an underappreciated role in the pathophysiology of these disease processes. Lipid peroxidation products are involved in the transcriptional regulation of endogenous anti-oxidant systems. Recent evidence demonstrates that transient increases in LPP may be beneficial in cardioprotection by contributing to mitohormesis (i.e. induction of anti-oxidant systems) in cardiomyocytes. Thus, exploitation of the cardioprotective actions of the LPP may represent a novel therapeutic strategy for future treatment of heart disease. © 2011 The Authors. Clinical and Experimental Pharmacology and Physiology © 2011 Blackwell Publishing Asia Pty Ltd.

  6. Tissue Trace Elements and Lipid Peroxidation in Breeding Female Bank Voles Myodes glareolus.

    Science.gov (United States)

    Bonda-Ostaszewska, Elżbieta; Włostowski, Tadeusz; Łaszkiewicz-Tiszczenko, Barbara

    2018-04-27

    Recent studies have demonstrated that reproduction reduces oxidative damage in various tissues of small mammal females. The present work was designed to determine whether the reduction of oxidative stress in reproductive bank vole females was associated with changes in tissue trace elements (iron, copper, zinc) that play an essential role in the production of reactive oxygen species. Lipid peroxidation (a marker of oxidative stress) and iron concentration in liver, kidneys, and skeletal muscles of reproducing bank vole females that weaned one litter were significantly lower than in non-reproducing females; linear regression analysis confirmed a positive relation between the tissue iron and lipid peroxidation. The concentrations of copper were significantly lower only in skeletal muscles of reproductive females and correlated positively with lipid peroxidation. No changes in tissue zinc were found in breeding females when compared with non-breeding animals. These data indicate that decreases in tissue iron and copper concentrations may be responsible for the reduction of oxidative stress in reproductive bank vole females.

  7. Lipid Peroxidation and Transforming Growth Factor-β1 Levels in Gastric Cancer at Pathologic Stages

    Directory of Open Access Journals (Sweden)

    Özgür Kemik

    2012-09-01

    Full Text Available Objective: High levels of TGF-β1 and enhanced TGF-β1 receptor signaling are related to the pathology of gastric cancer. This effect is caused by oxidative stress and lipid peroxidation products. The aim of this study was to investigate the levels of TGF-β1 and lipid peroxidation products in gastric cancer patients and their correlation with pathologic stage. Material and Methods: Lipid peroxidation products and TGF-β1 levels were studied in the serum samples of 50 gastric cancer patients and 18 control subjects.Results: HNE-protein adducts and TGF-β1 levels were significantly higher in T2, T3 and T4 gastric cancers than in either the T1 stage or controls (p<0.001. Pathologic stage was correlated with TGF-β1 levels (r=0.702, p<0.05.Conclusion: These markers production may contribute to tumor angiogenesis and aid in the prognosis of the gastric cancer.

  8. Age dependent effects of combined irradiation on lipid peroxidation in rat blood

    International Nuclear Information System (INIS)

    Mazhul', L.M.; Volykhina, V.E.; Gatsko, G.G.

    2000-01-01

    It was studied the effects of combined action of external acute gamma-irradiation in dose 1.0 Gy and chronic internal irradiation of cesium 137 (0.8 MBq/kg) on lipid peroxidation system in rat blood. Animals of two aged groups (2 and 6 months old) was investigated. The experiments were conducted on 10, 30, 90 and 180 days after the cessation of cesium 137 injection. Internal irradiation didn't exert influence on lipid peroxidation system in blood. Antioxidant system was activated on 10 days after acute irradiation at 2-months old animals and by 180 days at 6-months ones. In the case of combined irradiation activation of the antioxidant system in blood serum of 2-months old rats in early terms (10 days) possibly supports the invariable level of lipid peroxidation products. At 6-months old rats, on the contrary, the activation of the antioxidant system was not registered, however the content of malonic dialdehyde was increased. Possibly, at 2-months old rats the combined irradiation in early terms stimulates the protective systems of the organism in higher degree than at 6-months old ones

  9. Thermal Adaptation of the Archaeal and Bacterial Lipid Membranes

    Science.gov (United States)

    Koga, Yosuke

    2012-01-01

    The physiological characteristics that distinguish archaeal and bacterial lipids, as well as those that define thermophilic lipids, are discussed from three points of view that (1) the role of the chemical stability of lipids in the heat tolerance of thermophilic organisms: (2) the relevance of the increase in the proportion of certain lipids as the growth temperature increases: (3) the lipid bilayer membrane properties that enable membranes to function at high temperatures. It is concluded that no single, chemically stable lipid by itself was responsible for the adaptation of surviving at high temperatures. Lipid membranes that function effectively require the two properties of a high permeability barrier and a liquid crystalline state. Archaeal membranes realize these two properties throughout the whole biological temperature range by means of their isoprenoid chains. Bacterial membranes meet these requirements only at or just above the phase-transition temperature, and therefore their fatty acid composition must be elaborately regulated. A recent hypothesis sketched a scenario of the evolution of lipids in which the “lipid divide” emerged concomitantly with the differentiation of archaea and bacteria. The two modes of thermal adaptation were established concurrently with the “lipid divide.” PMID:22927779

  10. Thermal Adaptation of the Archaeal and Bacterial Lipid Membranes

    Directory of Open Access Journals (Sweden)

    Yosuke Koga

    2012-01-01

    Full Text Available The physiological characteristics that distinguish archaeal and bacterial lipids, as well as those that define thermophilic lipids, are discussed from three points of view that (1 the role of the chemical stability of lipids in the heat tolerance of thermophilic organisms: (2 the relevance of the increase in the proportion of certain lipids as the growth temperature increases: (3 the lipid bilayer membrane properties that enable membranes to function at high temperatures. It is concluded that no single, chemically stable lipid by itself was responsible for the adaptation of surviving at high temperatures. Lipid membranes that function effectively require the two properties of a high permeability barrier and a liquid crystalline state. Archaeal membranes realize these two properties throughout the whole biological temperature range by means of their isoprenoid chains. Bacterial membranes meet these requirements only at or just above the phase-transition temperature, and therefore their fatty acid composition must be elaborately regulated. A recent hypothesis sketched a scenario of the evolution of lipids in which the “lipid divide” emerged concomitantly with the differentiation of archaea and bacteria. The two modes of thermal adaptation were established concurrently with the “lipid divide.”

  11. Application of lipid peroxidation and protein oxidation biomarkers for oxidative damage in mammalian cells. A comparison with two fluorescent probes

    NARCIS (Netherlands)

    Orhan, H.; Gurer-Orhan, H.; Vriese, E.; Vermeulen, N.P.E.; Meerman, J.H.N.

    2006-01-01

    We recently developed two biomarker sets for oxidative damage: one for determination of lipid peroxidation (LPO) degradation products; acetaldehyde, propanal, butanal, pentanal, hexanal, heptanal, octanal, nonanal, malondialdehyde and acetone, by a gas chromatography-electron capture detection

  12. Lipid peroxidation and antioxidant activity in patients in labor with nonreassuring fetal status.

    Science.gov (United States)

    Dede, F S; Guney, Yildiz; Dede, Hulya; Koca, Cemile; Dilbaz, Berna; Bilgihan, Ayse

    2006-01-01

    The aim of our study was to evaluate lipid peroxidation products and antioxidant enzyme activity in placental tissue and umbilical cord blood, as a marker for fetal hypoxia in patients in labor with nonreassuring fetal status. Umbilical cord arterial blood and placental tissue samples were collected from 24 patients with term pregnancies in labor and nonreassuring fetal heart rate (FHR) patterns (study) and 24 women with normal pregnancies in labor and normal FHR tracings (controls) for determination of malondialdehyde (MDA) as a marker for lipid peroxidation and superoxide dismutase (SOD) for the antioxidant activity. Measured values were compared statistically between two groups using independent samples t-test or Mann-Whitney U-test. The median 1min Apgar score was 8 (range 4-9) in the study group and 9 (range 8-10) in the control group, respectively (p 0.05). Placental MDA levels in patients with nonreassuring fetal status were found to be significantly elevated compared to the control group (12.14 nmol/g tissue versus 9.75 nmol/g tissue; p < 0.01). The placental SOD activity in the study group was significantly higher (p < 0.01) compared to controls (3.57 U/mg protein versus 2.63 U/mg protein). The umbilical cord blood MDA levels in the study group were higher than in normal pregnancies (4.99 nmol/mL, 3.88 nmol/mL; p < 0.05). The activity of SOD in umbilical cord blood was significantly higher (p < 0.001) in patients with nonreassuring fetal status when compared with the control group (11.62 versus 6.95 U/mL). Lipid peroxidation products and antioxidant functions were elevated in the umbilical cord blood and placenta of patients having nonreassuring FHR tracings during labor. These findings indicate that lipid peroxidation products in placenta and umbilical cord blood can be used as a possible marker for fetal hypoxia during labor and SOD levels may discriminate acute from chronic hypoxia. Further investigations are needed with large number of series to

  13. Dose-rate and oxygen effects in models of lipid membranes: linoleic acid

    Energy Technology Data Exchange (ETDEWEB)

    Raleigh, J A; Kremers, W; Gaboury, B [Atomic Energy of Canada Ltd., Pinawa, Manitoba. Whiteshell Nuclear Research Establishment

    1977-03-01

    Cellular membranes have been suggested as possible loci for the development of the oxygen effect in radiobiology. Unsaturated lipids from membranes are subject to very efficient radiation-induced peroxidation, and the deleterious effects generally associated with lipid autoxidation could be initiated by ionizing radiation. Oxidative damage in lipids was characterized not only by high yields but also by a profound dose-rate effect. At dose-rates of x irradiation below 100 rad/min, a very sharp rise occurred in oxidative damage. This damage has been quantified spectrophotometrically in terms of diene conjugation (O.D. 234 mm) and chromatographically in terms of specific 9- and 13-hydroperoxide formation in linoleic acid micelles. Radical scavenging experiments indicated that hydroxyl radical attack initiated the oxidative damage. Dimethyl sulphoxide is exceptional in that it did not protect, but sensitized, linoleic acid to radiation-induced peroxidation. The yields of hydroperoxides were substantial (G = 10 to 40) and could be related to biological changes known to be effected by autoxidizing lipids.

  14. Some peculiarities of lipides peroxide oxidation and anti oxidation therapy of duodenal peptic ulcer in the persons who stayed in the zone of the Chernobyl accident

    International Nuclear Information System (INIS)

    Babak, O.Ya.; Chernyak, A.M.; Goncharova, L.Yi.; Pasyijeshvyilyi, L.M.

    1994-01-01

    The authors have studied the links of lipides peroxide oxidation (LPO) in the blood plasma, i.e. the level of antioxidant protection at duodenal peptic ulcer (DPU) in the persons who stayed in the zone of the accident at Chernobyl Atomic Power Station. LPO intensification takes place at the expense of the primary stages (spontaneous and hydrogen peroxide induced chemo luminescence) in the liquidators with DPU, when compared with the patients having DPU who did not stay in the zone of the accident. It suggests of exhaustion of cell membranes anti-oxidate protection level which provides atypical course of inflammatory processes in the gastrointestinal tract mucous membrane. The peculiarities of blood plasma LPO changes suggest that it would be reasonable to include antioxidants (Unithiolum) to the complex treatment of the liquidators

  15. Lipid clustering correlates with membrane curvature as revealed by molecular simulations of complex lipid bilayers.

    Directory of Open Access Journals (Sweden)

    Heidi Koldsø

    2014-10-01

    Full Text Available Cell membranes are complex multicomponent systems, which are highly heterogeneous in the lipid distribution and composition. To date, most molecular simulations have focussed on relatively simple lipid compositions, helping to inform our understanding of in vitro experimental studies. Here we describe on simulations of complex asymmetric plasma membrane model, which contains seven different lipids species including the glycolipid GM3 in the outer leaflet and the anionic lipid, phosphatidylinositol 4,5-bisphophate (PIP2, in the inner leaflet. Plasma membrane models consisting of 1500 lipids and resembling the in vivo composition were constructed and simulations were run for 5 µs. In these simulations the most striking feature was the formation of nano-clusters of GM3 within the outer leaflet. In simulations of protein interactions within a plasma membrane model, GM3, PIP2, and cholesterol all formed favorable interactions with the model α-helical protein. A larger scale simulation of a model plasma membrane containing 6000 lipid molecules revealed correlations between curvature of the bilayer surface and clustering of lipid molecules. In particular, the concave (when viewed from the extracellular side regions of the bilayer surface were locally enriched in GM3. In summary, these simulations explore the nanoscale dynamics of model bilayers which mimic the in vivo lipid composition of mammalian plasma membranes, revealing emergent nanoscale membrane organization which may be coupled both to fluctuations in local membrane geometry and to interactions with proteins.

  16. Application of FTIR-ATR Spectroscopy to Determine the Extent of Lipid Peroxidation in Plasma during Haemodialysis

    Directory of Open Access Journals (Sweden)

    Adam Oleszko

    2015-01-01

    Full Text Available During a haemodialysis (HD, because of the contact of blood with the surface of the dialyser, the immune system becomes activated and reactive oxygen species (ROS are released into plasma. Particularly exposed to the ROS are lipids and proteins contained in plasma, which undergo peroxidation. The main breakdown product of oxidized lipids is the malondialdehyde (MDA. A common method for measuring the concentration of MDA is a thiobarbituric acid reactive substances (TBARS method. Despite the formation of MDA in plasma during HD, its concentration decreases because it is removed from the blood in the dialyser. Therefore, this research proposes the Fourier Transform Infrared Attenuated Total Reflectance (FTIR-ATR spectroscopy, which enables determination of primary peroxidation products. We examined the influence of the amount of hydrogen peroxide added to lipid suspension that was earlier extracted from plasma specimen on lipid peroxidation with use of TBARS and FTIR-ATR methods. Linear correlation between these methods was shown. The proposed method was effective during the evaluation of changes in the extent of lipid peroxidation in plasma during a haemodialysis in sheep. A measurement using the FTIR-ATR showed an increase in plasma lipid peroxidation after 15 and 240 minutes of treatment, while the TBARS concentration was respectively lower.

  17. Effect of dietary docosahexaenoic acid connecting phospholipids on the lipid peroxidation of the brain in mice.

    Science.gov (United States)

    Hiratsuka, Seiichi; Ishihara, Kenji; Kitagawa, Tomoko; Wada, Shun; Yokogoshi, Hidehiko

    2008-12-01

    The effect of dietary docosahexaenoic acid (DHA, C22:6n-3) with two lipid types on lipid peroxidation of the brain was investigated in streptozotocin (STZ)-induced diabetic mice. Each group of female Balb/c mice was fed a diet containing DHA-connecting phospholipids (DHA-PL) or DHA-connecting triacylglycerols (DHA-TG) for 5 wk. Safflower oil was fed as the control. The lipid peroxide level of the brain was significantly lower in the mice fed the DHA-PL diet when compared to those fed the DHA-TG and safflower oil diets, while the alpha-tocopherol level was significantly higher in the mice fed the DHA-PL diet than in those fed the DHA-TG and safflower oil diets. The DHA level of phosphatidylethanolamine in the brain was significantly higher in the mice fed the DHA-PL diet than in those fed the safflower oil diet. The dimethylacetal levels were significantly higher in the mice fed the DHA-PL diet than in those fed the safflower oil and DHA-TG diets. These results suggest that the dietary DHA-connecting phospholipids have an antioxidant activity on the brain lipids in mice, and the effect may be related to the brain plasmalogen.

  18. Drinking orange juice increases total antioxidant status and decreases lipid peroxidation in adults.

    Science.gov (United States)

    Foroudi, Shahrzad; Potter, Andrew S; Stamatikos, Alexis; Patil, Bhimanagouda S; Deyhim, Farzad

    2014-05-01

    Cardiovascular disease (CVD) is the leading cause of death in the world and is the primary cause of mortality among Americans. One of the many reasons for the pathogenesis of CVD is attributed to eating diets high in saturated fat and refined carbohydrates and low in fruits and vegetables. Epidemiological evidence has supported a strong association between eating diets rich in fruits and vegetables and cardiovascular health. An experiment was conducted utilizing 24 adults with hypercholesterolemia and hypertriglyceridemia to evaluate the impact of drinking 20 fl oz of freshly squeezed orange juice daily for 90 days on blood pressure, lipid panels, plasma antioxidant capacity, metabolic hormones, lipid peroxidation, and inflammatory markers. Except for addition of drinking orange juice, subjects did not modify their eating habits. The findings suggested that drinking orange juice does not affect (P>.1) blood pressure, lipid panels, metabolic hormones, body fat percentage, or inflammatory markers. However, total plasma antioxidant capacity was significantly increased (Pjuice consumption. Drinking orange juice may protect the cardiovascular system by increasing total plasma antioxidant status and by lowering lipid peroxidation independent of other cardiovascular risk markers evaluated in this study.

  19. Effect of Cu2+ and pH on intracellular calcium content and lipid peroxidation in winter wheat roots

    Directory of Open Access Journals (Sweden)

    M. E. Riazanova

    2015-06-01

    Full Text Available The study investigates the effect of copper ions and pH of external solution on intracellular calcium homeostasis and lipid peroxidation in winter wheat roots. Experiment was carried out with winter wheat. Sterile seeds were germinated in Petri dishes on the filter paper soaked with acetic buffer (pH 4.7 and 6.2 at 20 °Cin the dark for 48 hours. Copper was added as CuSO4. It’s concentrations varied from 0 to 50 µM. The Ca2+-fluorescent dye Fluo-3/AM ester was loaded on 60 hour. Root fluorescence with Fluo-3 loading was detected using X-Cite Series 120 Q unit attached to microscope Olympus BX53 with camera Olympus DP72. Imaging of root cells was achieved after exciting with 488 nm laser and collection of emission signals above 512 nm. Preliminary analysis of the images was performed using software LabSens; brightness (fluorescence intensity analysis was carried out by means of ImageJ. Peroxidation of lipids was determined according to Kumar and Knowles method. It was found that pH of solution had effect on release of calcium from intracellular stores. Low pH provokes an increase of [Ca2+]cyt which may be reaction of roots to acidic medium. Copper induces increase in non-selective permeability of plasma membrane and leads to its faster depolarization. This probably initiates Ca-dependent depolarization channels which are responsible for the influx of calcium from apoplast into the cell. Changing of the membrane permeability may occur due to interaction between Cu2+ ions and Ca-binding sites on plasma membrane or may be due to binding of copper with sulfhydryl groups and increasing of POL. Copper may also damage lipid bilayer and change the activity of some non-selective channels and transporters. Reactive oxygen species which are formed under some types of stress factors, especially the effect of heavy metals, can be activators of Ca-channels. Cu2+ ions rise MDA content and promote the oxidative stress. Low medium pH also induces its

  20. Aerobic training suppresses exercise-induced lipid peroxidation and inflammation in overweight/obese adolescent girls.

    Science.gov (United States)

    Youssef, Hala; Groussard, Carole; Lemoine-Morel, Sophie; Pincemail, Joel; Jacob, Christophe; Moussa, Elie; Fazah, Abdallah; Cillard, Josiane; Pineau, Jean-Claude; Delamarche, Arlette

    2015-02-01

    This study aimed to determine whether aerobic training could reduce lipid peroxidation and inflammation at rest and after maximal exhaustive exercise in overweight/obese adolescent girls. Thirty-nine adolescent girls (14-19 years old) were classified as nonobese or overweight/obese and then randomly assigned to either the nontrained or trained group (12-week multivariate aerobic training program). Measurements at the beginning of the experiment and at 3 months consisted of body composition, aerobic fitness (VO2peak) and the following blood assays: pre- and postexercise lipid peroxidation (15F2a-isoprostanes [F2-Isop], lipid hydroperoxide [ROOH], oxidized LDL [ox-LDL]) and inflammation (myeloperoxidase [MPO]) markers. In the overweight/ obese group, the training program significantly increased their fat-free mass (FFM) and decreased their percentage of fat mass (%FM) and hip circumference but did not modify their VO2peak. Conversely, in the nontrained overweight/obese group, weight and %FM increased, and VO2peak decreased, during the same period. Training also prevented exercise-induced lipid peroxidation and/or inflammation in overweight/obese girls (F2-Isop, ROOH, ox-LDL, MPO). In addition, in the trained overweight/obese group, exercise-induced changes in ROOH, ox-LDL and F2-Isop were correlated with improvements in anthropometric parameters (waist-to-hip ratio, %FM and FFM). In conclusion aerobic training increased tolerance to exercise-induced oxidative stress in overweight/obese adolescent girls partly as a result of improved body composition.

  1. [Participation of final products of lipid peroxidation in the anticancer mechanism of ionizing radiation and radiomimetic cytostatics].

    Science.gov (United States)

    Przybyszewski, W M

    2001-01-01

    This review reports the evidence for the participation of final products of lipid peroxidation in the anticancer mechanism of ionising radiation and radiomimetic cytostatics. Processes of lipid peroxidation occur endogenously in response to oxidative stress and great diversity of reactive metabolites is formed. However, direct observation of radical reaction in pathophysiology of cells, tissues and organs is limited technically. Most investigations focused on the indirect assessment of their final products, aldehydes. The peroxidative breakdown of polyunsaturated fatty acids is believed to be involved in the regulation of cell division, and antitumor effect through biochemical and genetic processes.

  2. Reactive oxygen species and lipid peroxidation product-scavenging ability of yogurt organisms.

    Science.gov (United States)

    Lin, M Y; Yen, C L

    1999-08-01

    The antioxidative activity of the intracellular extracts of yogurt organisms was investigated. All 11 strains tested, including five strains of Streptococcus thermophilus and six strains of Lactobacillus delbrueckii ssp. bulgaricus, demonstrated an antioxidative effect on the inhibition of linoleic acid peroxidation. The antioxidative effect of intracellular extracts of 10(8) cells of yogurt organisms was equivalent to 25 to 96 ppm butylated hydroxytoluene, which indicated that all strains demonstrated excellent antioxidative activity. The scavenging of reactive oxygen species, hydroxyl radical, and hydrogen peroxide was studied for intracellular extracts of yogurt organisms. All strains showed reactive oxygen species-scavenging ability. Lactobacillus delbrueckii ssp. bulgaricus Lb demonstrated the highest hydroxyl radical-scavenging ability at 234 microM. Streptococcus thermophilus MC and 821 and L. delbrueckii ssp. bulgaricus 448 and 449 scavenged the most hydrogen peroxide at approximately 50 microM. The scavenging ability of lipid peroxidation products, t-butylhydroperoxide and malondialdehyde, was also evaluated. Results showed that the extracts were not able to scavenge the t-butylhydroperoxide. Nevertheless, malondialdehyde was scavenged well by most strains.

  3. Membrane curvature enables N-Ras lipid anchor sorting to liquid-ordered membrane phases

    DEFF Research Database (Denmark)

    Larsen, Jannik Bruun; Jensen, Martin Borch; Bhatia, Vikram Kjøller

    2015-01-01

    Trafficking and sorting of membrane-anchored Ras GTPases are regulated by partitioning between distinct membrane domains. Here, in vitro experiments and microscopic molecular theory reveal membrane curvature as a new modulator of N-Ras lipid anchor and palmitoyl chain partitioning. Membrane...

  4. Plasma thiobarbituric acid reactivity: reaction conditions and the role of iron, antioxidants and lipid peroxy radicals on the quantitation of plasma lipid peroxides

    Energy Technology Data Exchange (ETDEWEB)

    Wade, C.R.; van Rij, A.M.

    1988-01-01

    The effects of Fe/sup 3 +/, lipid peroxy radicals and the antioxidant butylated hydroxytoluene on the 2-thiobarbituric (TBA) acid quantitation of plasma lipid peroxides were investigated. Whole plasma and plasma fractions prepared by trichloroacetic acid (TCA) protein precipitation and lipid extraction, demonstrated markedly differing TBA reactivities in the presence or absence of added Fe/sup 3 +/. Examination of the spectral profiles of the TBA reacted whole plasma and TCA precipitated fractions demonstrated the presence of interfering compounds which gave rise to an artifactual increase in lipid peroxide concentrations. In contrast the TBA reacted lipid extracts had low levels of interfering compounds that could be removed by our previously described high pressure liquid chromatographic method. Further characterization of the TBA reactivity of the lipid extract showed that Fe/sup 3 +/ at an optimal concentration of 0.5 mM was necessary for the quantitative decomposition of the lipid peroxides to the TBA reactive product malondialdehyde (MDA). However the presence of Fe/sup 3 +/ resulted in further peroxidation of any unsaturated lipids present.

  5. Generation of volatile hydrocarbons as a measure of radiation-induced lipid peroxidation in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Dobbs, C R; Kumar, K S; Weiss, J F; Catravas, G N [Armed Forces Radiobiology Research Inst., Bethesda, MD (USA)

    1981-04-01

    Using gas chromatography techniques, pentane production from microsomes could be detected at gamma radiation doses as low as 50 Gy, but definite increases were observed only with the addition of the peroxidation promoter ADP-Fe. There was a small but linear increase in pentane production, and presumably lipid peroxidation, when nonirradiated microsomes alone were incubated. The addition of ADP-Fe induced a further production of pentane which was linear with incubation time. Radiation alone (700 and 2000 Gy) also induced pentane production, but the highest levels were observed with the combination of ADP-Fe and radiation. In microsomes irradiated with 700 Gy, the rate of pentane production was greatest during the first 100 min post-irradiation. In comparing radiation-induced pentane generation to the enzymatic-induced system, it was seen that pentane production was much greater in the latter system.

  6. [Changes of lipid peroxidation parameters in children being treated for cancer].

    Science.gov (United States)

    Kazanova, G V; Baĭkova, V N; Dumbraĭs, K O; Gracheva, I V; Durnov, L A; Gorozhanskaia, E G; Zakharova, N V; Kurmashov, V I; Belkina, B M

    1997-01-01

    Lipid peroxidation (LP) occurring in pediatric cancer patients receiving polychemotherapy has been investigated. Plasma level of malonic dialdehyde in children with retinoblastoma (Rtb) was found to drop while it remained unchanged in patients with acute lymphoblastic leukemia (ALL). The treatment caused different changes in the red cell catalase levels in said groups: the enzyme concentration increased in the Rtb patients in the course of therapy and decreased in the ALL group. A slight decline in alpha-tocopherol and retinol levels the Rtb group was matched by a relevant rise in blood-plasma in the ALL group. To adjust LP regulation and improve resistance, antioxidants should be given to pediatric cancer patients suffering peroxidation-related stress.

  7. Differential Effect of Plant Lipids on Membrane Organization

    Science.gov (United States)

    Grosjean, Kevin; Mongrand, Sébastien; Beney, Laurent; Simon-Plas, Françoise; Gerbeau-Pissot, Patricia

    2015-01-01

    The high diversity of the plant lipid mixture raises the question of their respective involvement in the definition of membrane organization. This is particularly the case for plant plasma membrane, which is enriched in specific lipids, such as free and conjugated forms of phytosterols and typical phytosphingolipids, such as glycosylinositolphosphoceramides. This question was here addressed extensively by characterizing the order level of membrane from vesicles prepared using various plant lipid mixtures and labeled with an environment-sensitive probe. Fluorescence spectroscopy experiments showed that among major phytosterols, campesterol exhibits a stronger ability than β-sitosterol and stigmasterol to order model membranes. Multispectral confocal microscopy, allowing spatial analysis of membrane organization, demonstrated accordingly the strong ability of campesterol to promote ordered domain formation and to organize their spatial distribution at the membrane surface. Conjugated sterol forms, alone and in synergy with free sterols, exhibit a striking ability to order membrane. Plant sphingolipids, particularly glycosylinositolphosphoceramides, enhanced the sterol-induced ordering effect, emphasizing the formation and increasing the size of sterol-dependent ordered domains. Altogether, our results support a differential involvement of free and conjugated phytosterols in the formation of ordered domains and suggest that the diversity of plant lipids, allowing various local combinations of lipid species, could be a major contributor to membrane organization in particular through the formation of sphingolipid-sterol interacting domains. PMID:25575593

  8. Novel Eicosapentaenoic Acid-derived F3-isoprostanes as Biomarkers of Lipid Peroxidation*

    Science.gov (United States)

    Song, Wen-Liang; Paschos, Georgios; Fries, Susanne; Reilly, Muredach P.; Yu, Ying; Rokach, Joshua; Chang, Chih-Tsung; Patel, Pranav; Lawson, John A.; FitzGerald, Garret A.

    2009-01-01

    Isoprostanes (iPs) are prostaglandin (PG) isomers generated by free radical-catalyzed peroxidation of polyunsaturated fatty acids (PUFAs). Urinary F2-iPs, PGF2α isomers derived from arachidonic acid (AA) are used as indices of lipid peroxidation in vivo. We now report the characterization of two major F3-iPs, 5-epi-8,12-iso-iPF3α-VI and 8,12-iso-iPF3α-VI, derived from the ω-3 fatty acid, eicosapentaenoic acid (EPA). Although the potential therapeutic benefits of EPA receive much attention, a shift toward a diet rich in ω-3 PUFAs may also predispose to enhanced lipid peroxidation. Urinary 5-epi-8,12-iso-iPF3α-VI and 8,12-iso-iPF3α-VI are highly correlated and unaltered by cyclooxygenase inhibition in humans. Fish oil dose-dependently elevates urinary F3-iPs in mice and a shift in dietary ω-3/ω-6 PUFAs is reflected by an increasing slope [m] of the line relating urinary 8, 12-iso-iPF3α-VI and 8,12-iso-iPF2α-VI. Administration of bacterial lipopolysaccharide evokes a reversible increase in both urinary 8,12-iso-iPF3α-VI and 8,12-iso-iPF2α-VI in humans on an ad lib diet. However, while excretion of the iPs is highly correlated (R2 median = 0.8), [m] varies by an order of magnitude, reflecting marked inter-individual variability in the relative peroxidation of ω-3 versus ω-6 substrates. Clustered analysis of F2- and F3-iPs refines assessment of the oxidant stress response to an inflammatory stimulus in vivo by integrating variability in dietary intake of ω-3/ω-6 PUFAs. PMID:19520854

  9. Non-Brownian diffusion in lipid membranes: Experiments and simulations.

    Science.gov (United States)

    Metzler, R; Jeon, J-H; Cherstvy, A G

    2016-10-01

    The dynamics of constituents and the surface response of cellular membranes-also in connection to the binding of various particles and macromolecules to the membrane-are still a matter of controversy in the membrane biophysics community, particularly with respect to crowded membranes of living biological cells. We here put into perspective recent single particle tracking experiments in the plasma membranes of living cells and supercomputing studies of lipid bilayer model membranes with and without protein crowding. Special emphasis is put on the observation of anomalous, non-Brownian diffusion of both lipid molecules and proteins embedded in the lipid bilayer. While single component, pure lipid bilayers in simulations exhibit only transient anomalous diffusion of lipid molecules on nanosecond time scales, the persistence of anomalous diffusion becomes significantly longer ranged on the addition of disorder-through the addition of cholesterol or proteins-and on passing of the membrane lipids to the gel phase. Concurrently, experiments demonstrate the anomalous diffusion of membrane embedded proteins up to macroscopic time scales in the minute time range. Particular emphasis will be put on the physical character of the anomalous diffusion, in particular, the occurrence of ageing observed in the experiments-the effective diffusivity of the measured particles is a decreasing function of time. Moreover, we present results for the time dependent local scaling exponent of the mean squared displacement of the monitored particles. Recent results finding deviations from the commonly assumed Gaussian diffusion patterns in protein crowded membranes are reported. The properties of the displacement autocorrelation function of the lipid molecules are discussed in the light of their appropriate physical anomalous diffusion models, both for non-crowded and crowded membranes. In the last part of this review we address the upcoming field of membrane distortion by elongated membrane

  10. Lateral mobility of plasma membrane lipids in dividing Xenopus eggs

    OpenAIRE

    Laat, S.W. de; Tetteroo, P.A.T.; Bluemink, J.G.; Dictus, W.J.A.G.; Zoelen, E.J.J. van

    1984-01-01

    The lateral mobility of plasma membrane lipids was analyzed during first cleavage of Xaopus Levis eggs by fluorescence photobleaching recovery (FPR) measurements, using the lipid analogs 5-(N-hexadecanoyl)aminofluorescein (“HEDAF”) and 5-(N-tetradecanoyl)aminofluorescein (“TEDAF”) as probes. The preexisting plasma membrane of the animal side showed an inhomogeneous, dotted fluorescence pattern after labeling and the lateral mobility of both probes used was below the detection limits of the FP...

  11. Importance of the hexagonal lipid phase in biological membrane organization

    OpenAIRE

    Jouhet, Juliette

    2013-01-01

    Domains are present in every natural membrane. They are characterized by a distinctive protein and/or lipid composition. Their size is highly variable from the nano- to the micrometer scale. The domains confer specific properties to the membrane leading to original structure and function. The determinants leading to domain organization are therefore important but remain obscure. This review presents how the ability of lipids to organize into hexagonal II or lamellar phases can promote particu...

  12. Atomistic study of lipid membranes containing chloroform: looking for a lipid-mediated mechanism of anesthesia.

    Directory of Open Access Journals (Sweden)

    Ramon Reigada

    Full Text Available The molecular mechanism of general anesthesia is still a controversial issue. Direct effect by linking of anesthetics to proteins and indirect action on the lipid membrane properties are the two hypotheses in conflict. Atomistic simulations of different lipid membranes subjected to the effect of small volatile organohalogen compounds are used to explore plausible lipid-mediated mechanisms. Simulations of homogeneous membranes reveal that electrostatic potential and lateral pressure transversal profiles are affected differently by chloroform (anesthetic and carbon tetrachloride (non-anesthetic. Simulations of structured membranes that combine ordered and disordered regions show that chloroform molecules accumulate preferentially in highly disordered lipid domains, suggesting that the combination of both lateral and transversal partitioning of chloroform in the cell membrane could be responsible of its anesthetic action.

  13. Immunoaffinity Knockout of Saponin Glycosides from Asparagus racemosus to Assess Anti-lipid Peroxidation.

    Science.gov (United States)

    Onlom, Churanya; Phrompittayarat, Watoo; Putalun, Waraporn; Waranuch, Neti; Ingkaninan, Kornkanok

    2017-07-01

    Asparagus racemosus Willd (Asparagaceae family), known as Shatavari, is important in Ayurveda and traditional Thai medicines. The saponin glycosides, shatavarin I and IV are major constituents in its roots and may be responsible for their actions including protection against lipid peroxidation and carcinogenesis. To develop an immunoaffinity column for isolating compounds with structures related to shatavarin IV from crude extracts of A. racemosus root. The monoclonal antibody recognising shatavarin IV (mAbShavIV) was coupled to an Affi-Gel Hz gel to isolate compounds with structures related to shatavarin IV from the other components of crude extracts of A. racemosus root. The saponin glycosides in each fraction were analysed by mAbShavIV ELISA and LC-MS/MS. The pooled wash-through fractions contained 3% of loaded mAbShavIV reactive saponin glycosides, while eluted fractions released ~ 90% of shatavarin saponin glycosides in a single step. Using thiobarbiturate (TBARs) to measure lipid-peroxidation, the extract, and the pooled wash-through fractions showed moderate protection against Cu + -induced oxidation of human low density lipoprotein (LDL) (IC 50 11.3 ± 1.4 and 12.6 ± 0.9 μg/mL, respectively). In contrast, the saponin glycosides eluted from the mAbShavIV-column had weaker protectant (IC 50 29.7 ± 1.8 μg/mL) suggesting that A. racemosus shatavarins do not inhibit carcinogenesis through preventing lipid peroxidation. The strategy described here demonstrates its utility for isolating a group of related compounds from the rest of the extract with selectivity and recovery rate. Pharmacological efficacy and synergistic effects of the components obtained can be further investigated. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  14. Impact of dietary oils and fats on lipid peroxidation in liver and blood of albino rats

    Science.gov (United States)

    Haggag, Mohammad El-Sayed Yassin El-Sayed; Elsanhoty, Rafaat Mohamed; Ramadan, Mohamed Fawzy

    2014-01-01

    Objective To investigate the effects of different dietary fat and oils (differing in their degree of saturation and unsaturation) on lipid peroxidation in liver and blood of rats. Methods The study was conducted on 50 albino rats that were randomly divided into 5 groups of 10 animals. The groups were fed on dietary butter (Group I), margarine (Group II), olive oil (Group III), sunflower oil (Group IV) and corn oil (Group V) for 7 weeks. After 12 h of diet removal, livers were excised and blood was collected to measure malondialdehyde (MDA) levels in the supernatant of liver homogenate and in blood. Blood superoxide dismutase activity (SOD), glutathione peroxidase activity (GPx), serum vitamin E and total antioxidant capacity (TAC) levels were also measured to determine the effects of fats and oils on lipid peroxidation. Results The results indicated that no significant differences were observed in SOD activity, vitamin E and TAC levels between the five groups. However, there was significant decrease of GPx activity in groups IV and V when compared with other groups. The results indicated that feeding corn oil caused significant increases in liver and blood MDA levels as compared with other oils and fats. There were positive correlations between SOD and GPx, vitamin E and TAC as well as between GPx and TAC (r: 0.743; P<0.001) and between blood MDA and liver MDA (r: 0.897; P<0.001). The results showed also negative correlations between blood MDA on one hand and SOD, GPx, vitamin E and TAC on the other hand. Conclusions The results demonstrated that feeding oils rich in polyunsaturated fatty acids (PUFA) increases lipid peroxidation significantly and may raise the susceptibility of tissues to free radical oxidative damage. PMID:24144131

  15. Lipid peroxidation inhibition and antiradical activities of some leaf fractions of Mangifera indica.

    Science.gov (United States)

    Badmus, Jelili A; Adedosu, Temitope O; Fatoki, John O; Adegbite, Victor A; Adaramoye, Oluwatosin A; Odunola, Oyeronke A

    2011-01-01

    This study was undertaken to assess in vitro lipid peroxidation inhibitions and anti-radical activities of methanolic, chloroform, ethyl acetate and water fractions of Mangifera indica leaf. Inhibition of Fe(2+)-induced lipid peroxidation (LPO) in egg, brain, and liver homogenates, 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl (OH-) radical scavenging activities were evaluated. Total phenol was assessed in all fractions, and the reducing power of methanolic fraction was compared to gallic acid and ascorbic acid. The results showed that Fe2+ induced significant lipid peroxidation (LPO) in all the homogenates. Ethyl acetate fraction showed the highest percentage inhibition of LPO in both egg yolk (68.3%) and brain (66.3%), while the aqueous fraction exerted the highest inhibition in liver homogenate (89.1%) at a concentration of 10 microg/mL. These observed inhibitions of LPO by these fractions were higher than that of ascorbic acid used as a standard. The DPPH radical scavenging ability exhibited by ethyl acetate fraction was found to be the highest with IC50 value of 1.5 microg/mL. The ethyl acetate and methanolic fractions had the highest OH- radical scavenging ability with the same IC50 value of 5 microg/mL. The total phenol content of ethyl acetate fraction was the highest with 0.127 microg/mg gallic acid equivalent (GAE). The reductive potential of methanolic fraction showed a concentration-dependent increase. This study showed that inhibition of LPO and the DPPH and OH- radicals scavenging abilities of Mangifera indica leaf could be related to the presence of phenolic compounds. Therefore, the ethyl acetate fraction of the leaf may be a good source of natural antioxidative agent.

  16. Effects of Acetate-Free Citrate Dialysate on Glycoxidation and Lipid Peroxidation Products in Hemodialysis Patients

    Directory of Open Access Journals (Sweden)

    Atsumi Masuda

    2012-09-01

    Full Text Available Background/Aims: Previous studies have shown the presence of high levels of glycoxidation and lipid peroxidation products in association with atherosclerosis in patients with end-stage kidney disease. Acetates are commonly used buffer for correcting metabolic acidosis in hemodialysis (HD patients. Since the toxic effects of acetates are well established, acetate-free citrate dialysate (AFD has become available in Japan. The objective of the present study was to evaluate the suppressive effects of AFD on oxidative stress in maintenance HD patients by measuring plasma pentosidine and malondialdehyde-modified low-density lipoprotein (MDA-LDL levels as markers for glycoxidation and lipid peroxidation products. Methods: Plasma pentosidine, MDA-LDL and other laboratory parameters were examined on maintenance HD at the Juntendo University Hospital before and after switching to AFD. Results: MDA-LDL levels divided by LDL cholesterol were significantly lower than those before switching to AFD. Furthermore, levels of plasma pentosidine were lower than those before switching to AFD. Stepwise multiple regression analysis revealed that the percent change of the calcium-phosphorus product in the nondiabetic group and that of phosphorus in the diabetic group were predictive variables for the percent change of MDA-LDL/LDL, whereas the percent change of log high-sensitive C-reactive protein and that of systolic blood pressure in the nondiabetic group and that of diastolic blood pressure in the diabetic group were predictive variables for the percent change of plasma pentosidine. Conclusions: It appears that AFD decreases glycoxidation and lipid peroxidation products when compared with acid citrate dextrose in HD patients. The reduction of oxidative stress by AFD during HD may have possible beneficial effects on atherosclerosis through calcium-phosphorus metabolism and blood pressure.

  17. EFFECT OF PHYSICAL EXERCISE ON LIPID PEROXIDATION AND ANTIOXIDANT ASCORBIC ACID DEFENSE

    Directory of Open Access Journals (Sweden)

    Ljiljana M. Popović

    2006-06-01

    Full Text Available Strenuous exercises greatly increase oxygen consumption in the whole body, especially in skeletal muscles. Large part of oxygen consumption is reduced to H2O and ATP, but smaller part (2-5% results in an increased leakage of electrons from the mitochondrial respiratory chain, forming various reactive oxygen species ─ ROS (O2˙¯, H2O2 i OH˙. These free radicals are capable of triggering a chain of damaging biochemical and physiological reactions (oxidative stress, lipid peroxidation,as a base for skeletal muscles damage after exercise. MDA (malondialdehide is a marker of exercise induced lipid peroxidation process. L–ascorbic acid is a major aqueous-phase antioxidant. To estimate antioxidant role of ascorbic acid we use rate between dehidroascorbate and ascorbate. In this paper those markers were determinated in 30 students, in rest and after treadmill running protocol (Bruce Treadmill Protocol. It was found that after the treadmill test , plasma MDA level had increased from 3,04 to 4,39 μM/L. Plasma ascorbic acid was also found to be higher after the treadmill test comparing to rest level (from 55,4 to 67,6 μM/L. DHA/A level in rest was 1,62 and after treadmill test it increased to 2,05. These results suggests that strenuous exercise increased process of lipid peroxidation, but in the same time increased ascorbic acid level in plasma and DHA/A rate indicates stronger antioxidant defense system.

  18. Simulations of simple linoleic acid-containing lipid membranes and models for the soybean plasma membranes.

    Science.gov (United States)

    Zhuang, Xiaohong; Ou, Anna; Klauda, Jeffery B

    2017-06-07

    The all-atom CHARMM36 lipid force field (C36FF) has been tested with saturated, monounsaturated, and polyunsaturated lipids; however, it has not been validated against the 18:2 linoleoyl lipids with an unsaturated sn-1 chain. The linoleoyl lipids are common in plants and the main component of the soybean membrane. The lipid composition of soybean plasma membranes has been thoroughly characterized with experimental studies. However, there is comparatively less work done with computational modeling. Our molecular dynamics (MD) simulation results show that the pure linoleoyl lipids, 1-stearoyl-2-linoleoyl-sn-glycero-3-phosphocholine (18:0/18:2) and 1,2-dilinoleoyl-sn-glycero-3-phosphocholine (di-18:2), agree very well with the experiments, which demonstrates the accuracy of the C36FF for the computational study of soybean membranes. Based on the experimental composition, the soybean hypocotyl and root plasma membrane models are developed with each containing seven or eight types of linoleoyl phospholipids and two types of sterols (sitosterol and stigmasterol). MD simulations are performed to characterize soybean membranes, and the hydrogen bonds and clustering results demonstrate that the lipids prefer to interact with the lipids of the same/similar tail unsaturation. All the results suggest that these two soybean membrane models can be used as a basis for further research in soybean and higher plant membranes involving membrane-associated proteins.

  19. Aspirin Increases the Solubility of Cholesterol in Lipid Membranes

    Science.gov (United States)

    Alsop, Richard; Barrett, Matthew; Zheng, Sonbo; Dies, Hannah; Rheinstadter, Maikel

    2014-03-01

    Aspirin (ASA) is often prescribed for patients with high levels of cholesterol for the secondary prevention of myocardial events, a regimen known as the Low-Dose Aspirin Therapy. We have recently shown that Aspirin partitions in lipid bilayers. However, a direct interplay between ASA and cholesterol has not been investigated. Cholesterol is known to insert itself into the membrane in a dispersed state at moderate concentrations (under ~37.5%) and decrease fluidity of membranes. We prepared model lipid membranes containing varying amounts of both ASA and cholesterol molecules. The structure of the bilayers as a function of ASA and cholesterol concentration was determined using high-resolution X-ray diffraction. At cholesterol levels of more than 40mol%, immiscible cholesterol plaques formed. Adding ASA to the membranes was found to dissolve the cholesterol plaques, leading to a fluid lipid bilayer structure. We present first direct evidence for an interaction between ASA and cholesterol on the level of the cell membrane.

  20. Lateral mobility of plasma membrane lipids in dividing Xenopus eggs

    NARCIS (Netherlands)

    Laat, S.W. de; Tetteroo, P.A.T.; Bluemink, J.G.; Dictus, W.J.A.G.; Zoelen, E.J.J. van

    1984-01-01

    The lateral mobility of plasma membrane lipids was analyzed during first cleavage of Xaopus Levis eggs by fluorescence photobleaching recovery (FPR) measurements, using the lipid analogs 5-(N-hexadecanoyl)aminofluorescein (“HEDAF”) and 5-(N-tetradecanoyl)aminofluorescein (“TEDAF”) as probes. The

  1. Steady-state oxidation of cholesterol catalyzed by cholesterol oxidase in lipid bilayer membranes on platinum electrodes

    International Nuclear Information System (INIS)

    Bokoch, Michael P.; Devadoss, Anando; Palencsar, Mariela S.; Burgess, James D.

    2004-01-01

    Cholesterol oxidase is immobilized in electrode-supported lipid bilayer membranes. Platinum electrodes are initially modified with a self-assembled monolayer of thiolipid. A vesicle fusion method is used to deposit an outer leaflet of phospholipids onto the thiolipid monolayer forming a thiolipid/lipid bilayer membrane on the electrode surface. Cholesterol oxidase spontaneously inserts into the electrode-supported lipid bilayer membrane from solution and is consequently immobilized to the electrode surface. Cholesterol partitions into the membrane from buffer solutions containing cyclodextrin. Cholesterol oxidase catalyzes the oxidation of cholesterol by molecular oxygen, forming hydrogen peroxide as a product. Amperometric detection of hydrogen peroxide for continuous solution flow experiments are presented, where flow was alternated between cholesterol solution and buffer containing no cholesterol. Steady-state anodic currents were observed during exposures of cholesterol solutions ranging in concentration from 10 to 1000 μM. These data are consistent with the Michaelis-Menten kinetic model for oxidation of cholesterol as catalyzed by cholesterol oxidase immobilized in the lipid bilayer membrane. The cholesterol detection limit is below 1 μM for cholesterol solution prepared in buffered cyclodextrin. The response of the electrodes to low density lipoprotein solutions is increased upon addition of cyclodextrin. Evidence for adsorption of low density lipoprotein to the electrode surface is presented

  2. Changes of nitric oxide system and lipid peroxidation parameters in the digestive system of rats under conditions of acute stress, and use of nonsteroidal anti-inflammatory drugs

    Directory of Open Access Journals (Sweden)

    Fomenko Iryna

    2015-03-01

    Full Text Available The use of nonsteroidal anti-inflammatory drugs (NSAIDs in combination with being physiologically stressed often occurs in in the course of different pathologies. This situation may result in the alteration of digestive system functioning. The effect of stress brings about changes in the activity of nitric oxide synthase (NOS, arginase, cyclooxygenase (COX and lipid peroxidation, whereas the use of NSAIDs interrupts the multiple functions of the cell via the inhibition of prostaglandins (PGs synthesis. Taking into account that NOS and COX-systems are connected in their regulation, the aim of the study was to determine the role played by NOS and lipid peroxidation under conditions of the combined action of NSAIDs and stress. In our study, male rats were used. The NSAIDs (naproxen - a non-selective COX inhibitor, celecoxib - a selective COX-2 blocker, and the compound 2A5DHT (which is the active substance of dual COX, and the lipoxygenase (LOX inhibitor, darbufelone were all administered at a dose 10 mg/kg, prior to water restraint stress (WRS. WRS brought about an increase of inducible NOS (iNOS activity in the intestinal mucosal and muscular membranes, as well as in the pancreas. Because of this, constitutive NOS izoform (cNOS and arginase activities decreased. Moreover, the MDA concentration increased, indicating the development of oxidative stress. In our work, pretreatment with naproxen, as in the WRS model, engendered a decrease in iNOS activity. What is more, administration of Celecoxib did not change iNOS activity, as compared to WRS alone, and it showed a tendency to reduce lipid peroxidation. In addition, 2A5DHT prior WRS brought about a decrease of iNOS activity, with the subsequent rise of cNOS activity. Of note, MDA concentration decreased in all studied organs, indicating the reduction of lipid peroxidation under the action of the darbufelone active substance.

  3. Membrane Compartmentalization Reducing the Mobility of Lipids and Proteins within a Model Plasma Membrane.

    Science.gov (United States)

    Koldsø, Heidi; Reddy, Tyler; Fowler, Philip W; Duncan, Anna L; Sansom, Mark S P

    2016-09-01

    The cytoskeleton underlying cell membranes may influence the dynamic organization of proteins and lipids within the bilayer by immobilizing certain transmembrane (TM) proteins and forming corrals within the membrane. Here, we present coarse-grained resolution simulations of a biologically realistic membrane model of asymmetrically organized lipids and TM proteins. We determine the effects of a model of cytoskeletal immobilization of selected membrane proteins using long time scale coarse-grained molecular dynamics simulations. By introducing compartments with varying degrees of restraints within the membrane models, we are able to reveal how compartmentalization caused by cytoskeletal immobilization leads to reduced and anomalous diffusional mobility of both proteins and lipids. This in turn results in a reduced rate of protein dimerization within the membrane and of hopping of membrane proteins between compartments. These simulations provide a molecular realization of hierarchical models often invoked to explain single-molecule imaging studies of membrane proteins.

  4. Exposure to Anacardiaceae Volatile Oils and Their Constituents Induces Lipid Peroxidation within Food-Borne Bacteria Cells

    Directory of Open Access Journals (Sweden)

    Ricardo M. Montanari

    2012-08-01

    Full Text Available The chemical composition of the volatile oils from five Anacardiaceae species and their activities against Gram positive and negative bacteria were assessed. The peroxidative damage within bacterial cell membranes was determined through the breakdown product malondialdehyde (MDA. The major constituents in Anacardium humile leaves oil were (E-caryophyllene (31.0% and α-pinene (22.0%, and in Anacardium occidentale oil they were (E-caryophyllene (15.4% and germacrene-D (11.5%. Volatile oil from Astronium fraxinifolium leaves were dominated by (E-β-ocimene (44.1% and α-terpinolene (15.2%, whilst the oil from Myracrodruon urundeuva contained an abundance of δ-3-carene (78.8%. However, Schinus terebinthifolius leaves oil collected in March and July presented different chemical compositions. The oils from all species, except the one from A. occidentale, exhibited varying levels of antibacterial activity against Staphylococcus aureus, Bacillus cereus and Escherichia coli. Oil extracted in July from S. terebinthifolius was more active against all bacterial strains than the corresponding oil extracted in March. The high antibacterial activity of the M. urundeuva oil could be ascribed to its high δ-3-carene content. The amounts of MDA generated within bacterial cells indicate that the volatile oils induce lipid peroxidation. The results suggest that one putative mechanism of antibacterial action of these volatile oils is pro-oxidant damage within bacterial cell membrane explaining in part their preservative properties.

  5. Protective effect of ascorbic acid on netilmicin-induced lipid profile and peroxidation parameters in rabbit blood plasma.

    Science.gov (United States)

    Devbhuti, Pritesh; Sikdar, Debasis; Saha, Achintya; Sengupta, Chandana

    2011-01-01

    A drug may cause alteration in blood-lipid profile and induce lipid peroxidation phenomena on administration in the body. Antioxidant may play beneficial role to control the negative alteration in lipid profile and lipid peroxidation. In view of this context, the present in vivo study was carried out to evaluate the role of ascorbic acid as antioxidant on netilmicin-induced alteration of blood lipid profile and peroxidation parameters. Rabbits were used as experimental animals and blood was collected to estimate blood-lipid profiles, such as total cholesterol (TCh), high density lipoprotein cholesterol (HDL-Ch), low density lipoprotein cholesterol (LDL-Ch), very low density lipoprotein cholesterol (VLDL-Ch), triglycerides (Tg), phospholipids (PL), and total lipids (TL), as well as peroxidation parameters, such as malondialdehyde (MDA), 4-hydroxy-2-nonenal (HNE), reduced glutathione (GSH) and nitric oxide (NO). The results revealed that netilmicin caused significant enhancement of MDA, HNE, TCh, LDL-Ch, VLDL-Ch, Tg levels and reduction in GSH, NO, HDL-Ch, PL, TL levels. On co-administration, ascorbic acid was found to be effective in reducing netilmicin-induced negative alterations of the above parameters.

  6. Aldehyde-sequestering drugs: tools for studying protein damage by lipid peroxidation products.

    Science.gov (United States)

    Burcham, Philip C; Kaminskas, Lisa M; Fontaine, Frank R; Petersen, Dennis R; Pyke, Simon M

    2002-12-27

    Elevated levels of reactive alpha,beta-unsaturated aldehydes (e.g. malondialdehyde, 4-hydroxynonenal and acrolein) in the affected tissues of various degenerative conditions suggest these substances are active propagators of the disease process. One experimental approach to attenuating damage by these intermediates employs 'aldehyde-sequestering drugs' as sacrificial nucleophiles, thereby sparing cell macromolecules and perhaps slowing disease progression. Drugs with demonstrated trapping activity toward lipid-derived aldehydes include various amine compounds such as aminoguanidine, carnosine and pyridoxamine. We have focused on identifying scavengers of acrolein, perhaps the most toxic aldehyde formed during lipid peroxidation cascades. Various phthalazine compounds (hydralazine and dihydralazine) were found to trap acrolein readily, forming hydrazone derivatives in a rapid Schiff-type reaction. These compounds strongly protect against acrolein-mediated toxicity in isolated hepatocytes.

  7. Influence of dihydroquercetin on the lipid peroxidation of mice during post-radiation period

    Energy Technology Data Exchange (ETDEWEB)

    Teselkin, Yu. O.; Babenkova, I. V.; Tjukavkina, N. A.; Rulenko, I. A.; Kolesnik, Yu. A.; Kolhir, V. K.; Eichholz, A. A. [Department of Biophysics, Russian Medical University, Ostrovityanova Street 1, Moscow 117869 (Russian Federation)

    1998-07-01

    The effect of the natural antioxidant dihydroquercetin was examined on the process of free radical oxidation of serum and liver lipids of mice, after a single 4 Gy dose of γ-irradiation. The content of lipid peroxidation products reacting with thiobarbituric acid in irradiated animals receiving oral dihydroquercetin (experimental) for 155 days after irradiation was significantly lower compared with animals receiving irradiation and no antioxidant (controls). The intensity of Fe{sup 2+}-induced chemiluminescence of liver homogenates of experimental mice was lower by the end of the experiment (p < 0.001) than the chemiluminescence of liver homogenates of both control and intact animals. It is assumed that this was due to the preferential uptake of dihydroquercetin by the liver. (author)

  8. Single Lipid Molecule Dynamics on Supported Lipid Bilayers with Membrane Curvature

    Directory of Open Access Journals (Sweden)

    Philip P. Cheney

    2017-03-01

    Full Text Available The plasma membrane is a highly compartmentalized, dynamic material and this organization is essential for a wide variety of cellular processes. Nanoscale domains allow proteins to organize for cell signaling, endo- and exocytosis, and other essential processes. Even in the absence of proteins, lipids have the ability to organize into domains as a result of a variety of chemical and physical interactions. One feature of membranes that affects lipid domain formation is membrane curvature. To directly test the role of curvature in lipid sorting, we measured the accumulation of two similar lipids, 1,2-Dihexadecanoyl-sn-glycero-3-phosphoethanolamine (DHPE and hexadecanoic acid (HDA, using a supported lipid bilayer that was assembled over a nanopatterned surface to obtain regions of membrane curvature. Both lipids studied contain 16 carbon, saturated tails and a head group tag for fluorescence microscopy measurements. The accumulation of lipids at curvatures ranging from 28 nm to 55 nm radii was measured and fluorescein labeled DHPE accumulated more than fluorescein labeled HDA at regions of membrane curvature. We then tested whether single biotinylated DHPE molecules sense curvature using single particle tracking methods. Similar to groups of fluorescein labeled DHPE accumulating at curvature, the dynamics of single molecules of biotinylated DHPE was also affected by membrane curvature and highly confined motion was observed.

  9. Concerted diffusion of lipids in raft-like membranes

    NARCIS (Netherlands)

    Apajalahti, Touko; Niemela, Perttu; Govindan, Praveen Nedumpully; Miettinen, Markus S.; Salonen, Emppu; Marrink, Siewert-Jan; Vattulainen, Ilpo

    2010-01-01

    Currently, there is no comprehensive model for the dynamics of cellular membranes. The understanding of even the basic dynamic processes, such as lateral diffusion of lipids, is still quite limited. Recent studies of one-component membrane systems have shown that instead of single-particle motions,

  10. Differential sensitivity of cellular membranes to peroxidative processes. An electronmicroscopic, histochemical and cytochemical study of the effects of vitamin E deficiency and X-irradiation on the liver of the Pekin duckling

    Energy Technology Data Exchange (ETDEWEB)

    Huijbers, W A.R.

    1976-01-01

    A description is given of a morphological and cytochemical investigation into the effects of both vitamin E deficiency and x irradiation on the ultrastructure and enzyme activities of several cellular membranes, particularly the plasma membrane and the membranes of lysosomes, mitochondria and endoplasmic reticulum. In the vitamin E deficient situation, the radicals and peroxides only originate near mitochondria and endoplasmic reticulum, so that these membrane systems suffer from changes. After irradiation of the liver of both the control duckling and the deficient duckling, radicals originate in all parts of the cell. Due to their high content of lipids and cholesterols, peroxides will occur mainly in plasma membranes and lysosomal membranes. Moreover, in these membranes there is hardly any protection by vitamin E.

  11. Changes in non-enzymatic antioxidant capacity and lipid peroxidation during germination of white, yellow and purple maize seeds

    International Nuclear Information System (INIS)

    Deng, B.; Zhang, Y.; Yang, K.

    2016-01-01

    In this study, the changes in non-enzymatic antioxidant capacity and lipid peroxidation during the germination process of purple, yellow and white maize seeds were compared, under favorable conditions. Results showed that germination can increase non-enzymatic antioxidant capacity (evaluated with ferric reducing power and 2, 2-diphenyl-1-picryl-hydrazyl-hydrate radical scavenging capacity) and lipid peroxidation levels for all these seeds. In addition, non-enzymatic antioxidant capacity observed in the germinating seeds were in the order of purple > yellow > white. However, the highest and lowest levels of lipid peroxidation could be seen during the germination processes of the white and purple seeds, respectively. In addition, the germination rates of the seeds followed the order of white > yellow > purple. Further studies showed that H/sub 2/O/sub 2/ treatment can significantly promote seed germination, especially for purple seeds. In addition, DMTU (dimethylthiourea), a specific scavenger for H/sub 2/O/sub 2/, could slightly but significantly arrest dormancy release. Data analysis showed that a high negative correlation (R/sup 2/ = -0.955) existed between non-enzymatic antioxidant capacity and germination rates. However, a high positive correlation (R/sup 2/ = 0.860) could be detected between lipid peroxidation and germination rates. Finally, lipid peroxidation as a possible novel signaling mechanism for seed germination has been discussed under stress-free conditions. (author)

  12. Effects of Dietary Lycopene Supplementation on Plasma Lipid Profile, Lipid Peroxidation and Antioxidant Defense System in Feedlot Bamei Lamb.

    Science.gov (United States)

    Jiang, Hongqin; Wang, Zhenzhen; Ma, Yong; Qu, Yanghua; Lu, Xiaonan; Luo, Hailing

    2015-07-01

    Lycopene, a red non-provitamin A carotenoid, mainly presenting in tomato and tomato byproducts, has the highest antioxidant activity among carotenoids because of its high number of conjugated double bonds. The objective of this study was to investigate the effect of lycopene supplementation in the diet on plasma lipid profile, lipid peroxidation and antioxidant defense system in feedlot lamb. Twenty-eight Bamei male lambs (90 days old) were divided into four groups and fed a basal diet (LP0, 40:60 roughage: concentrate) or the basal diet supplemented with 50, 100, and 200 mg/kg lycopene. After 120 days of feeding, all lambs were slaughtered and sampled. Dietary lycopene supplementation significantly reduced the levels of plasma total cholesterol (p0.05). The levels of TG (pCAT, pCAT (p<0.05, linearly) and SOD (p<0.001, linearly). Therefore, it was concluded that lycopene supplementation improved the antioxidant status of the lamb and optimized the plasma lipid profile, the dosage of 200 mg lycopene/kg feed might be desirable for growing lambs to prevent environment stress and maintain normal physiological metabolism.

  13. Influence of membrane phospholipid composition and structural organization on spontaneous lipid transfer between membranes.

    Science.gov (United States)

    Pankov, R; Markovska, T; Antonov, P; Ivanova, L; Momchilova, A

    2006-09-01

    Investigations were carried out on the influence of phospholipid composition of model membranes on the processes of spontaneous lipid transfer between membranes. Acceptor vesicles were prepared from phospholipids extracted from plasma membranes of control and ras-transformed fibroblasts. Acceptor model membranes with manipulated levels of phosphatidylethanolamine (PE), sphingomyelin and phosphatidic acid were also used in the studies. Donor vesicles were prepared of phosphatidylcholine (PC) and contained two fluorescent lipid analogues, NBD-PC and N-Rh-PE, at a self-quenching concentration. Lipid transfer rate was assessed by measuring the increase of fluorescence in acceptor membranes due to transfer of fluorescent lipid analogues from quenched donor to unquenched acceptor vesicles. The results showed that spontaneous NBD-PC transfer increased upon fluidization of acceptor vesicles. In addition, elevation of PE concentration in model membranes was also accompanied by an increase of lipid transfer to all series of acceptor vesicles. The results are discussed with respect to the role of lipid composition and structural order of cellular plasma membranes in the processes of spontaneous lipid exchange between membrane bilayers.

  14. Understanding carbon nanotube channel formation in the lipid membrane

    Science.gov (United States)

    Choi, Moon-ki; Kim, Hyunki; Lee, Byung Ho; Kim, Teayeop; Rho, Junsuk; Kim, Moon Ki; Kim, Kyunghoon

    2018-03-01

    Carbon nanotubes (CNTs) have been considered a prominent nano-channel in cell membranes because of their prominent ion-conductance and ion-selectivity, offering agents for a biomimetic channel platform. Using a coarse-grained molecular dynamics simulation, we clarify a construction mechanism of vertical CNT nano-channels in a lipid membrane for a long period, which has been difficult to observe in previous CNT-lipid interaction simulations. The result shows that both the lipid coating density and length of CNT affect the suitable fabrication condition for a vertical and stable CNT channel. Also, simulation elucidated that a lipid coating on the surface of the CNT prevents the CNT from burrowing into the lipid membrane and the vertical channel is stabilized by the repulsion force between the lipids in the coating and membrane. Our study provides an essential understanding of how CNTs can form stable and vertical channels in the membrane, which is important for designing new types of artificial channels as biosensors for bio-fluidic studies.

  15. Affinity of four polar neurotransmitters for lipid bilayer membranes

    DEFF Research Database (Denmark)

    Wang, Chunhua; Ye, Fengbin; Valardez, Gustavo F.

    2011-01-01

    . The simulations suggest that this attraction mainly relies on electrostatic interactions of the amino group of the neurotransmitter and the lipid phosphate. We conclude that moderate attraction to lipid membranes occurs for some polar neurotransmitters and hence that one premise for a theory of bilayer-mediated......Weak interactions of neurotransmitters and the lipid matrix in the synaptic membrane have been hypothesized to play a role in synaptic transmission of nerve signals, particularly with respect to receptor desensitization (Cantor, R. S. Biochemistry 2003, 42, 11891). The strength of such interactions......, however, was not measured, and this is an obvious impediment for further evaluation and understanding of a possible role for desensitization. We have used dialysis equilibrium to directly measure the net affinity of selected neurotransmitters for lipid membranes and analyzed this affinity data...

  16. A layer model of ethanol partitioning into lipid membranes.

    Science.gov (United States)

    Nizza, David T; Gawrisch, Klaus

    2009-06-01

    The effect of membrane composition on ethanol partitioning into lipid bilayers was assessed by headspace gas chromatography. A series of model membranes with different compositions have been investigated. Membranes were exposed to a physiological ethanol concentration of 20 mmol/l. The concentration of membranes was 20 wt% which roughly corresponds to values found in tissue. Partitioning depended on the chemical nature of polar groups at the lipid/water interface. Compared to phosphatidylcholine, lipids with headgroups containing phosphatidylglycerol, phosphatidylserine, and sphingomyelin showed enhanced partitioning while headgroups containing phosphatidylethanolamine resulted in a lower partition coefficient. The molar partition coefficient was independent of a membrane's hydrophobic volume. This observation is in agreement with our previously published NMR results which showed that ethanol resides almost exclusively within the membrane/water interface. At an ethanol concentration of 20 mmol/l in water, ethanol concentrations at the lipid/water interface are in the range from 30-15 mmol/l, corresponding to one ethanol molecule per 100-200 lipids.

  17. Effects of Iron Overload on the Activity of Na,K-ATPase and Lipid Profile of the Human Erythrocyte Membrane.

    Directory of Open Access Journals (Sweden)

    Leilismara Sousa

    Full Text Available Iron is an essential chemical element for human life. However, in some pathological conditions, such as hereditary hemochromatosis type 1 (HH1, iron overload induces the production of reactive oxygen species that may lead to lipid peroxidation and a change in the plasma-membrane lipid profile. In this study, we investigated whether iron overload interferes with the Na,K-ATPase activity of the plasma membrane by studying erythrocytes that were obtained from the whole blood of patients suffering from iron overload. Additionally, we treated erythrocytes of normal subjects with 0.8 mM H2O2 and 1 μM FeCl3 for 24 h. We then analyzed the lipid profile, lipid peroxidation and Na,K-ATPase activity of plasma membranes derived from these cells. Iron overload was more frequent in men (87.5% than in women and was associated with an increase (446% in lipid peroxidation, as indicated by the amount of the thiobarbituric acid reactive substances (TBARS and an increase (327% in the Na,K-ATPase activity in the plasma membrane of erythrocytes. Erythrocytes treated with 1 μM FeCl3 for 24 h showed an increase (132% in the Na,K-ATPase activity but no change in the TBARS levels. Iron treatment also decreased the cholesterol and phospholipid content of the erythrocyte membranes and similar decreases were observed in iron overload patients. In contrast, erythrocytes treated with 0.8 mM H2O2 for 24 h showed no change in the measured parameters. These results indicate that erythrocytes from patients with iron overload exhibit higher Na,K-ATPase activity compared with normal subjects and that this effect is specifically associated with altered iron levels.

  18. Plasma membrane lipids and their role in fungal virulence.

    Science.gov (United States)

    Rella, Antonella; Farnoud, Amir M; Del Poeta, Maurizio

    2016-01-01

    There has been considerable evidence in recent years suggesting that plasma membrane lipids are important regulators of fungal pathogenicity. Various glycolipids have been shown to impart virulent properties in several fungal species, while others have been shown to play a role in host defense. In addition to their role as virulence factors, lipids also contribute to other virulence mechanisms such as drug resistance, biofilm formation, and release of extracellular vesicles. In addition, lipids also affect the mechanical properties of the plasma membrane through the formation of packed microdomains composed mainly of sphingolipids and sterols. Changes in the composition of lipid microdomains have been shown to disrupt the localization of virulence factors and affect fungal pathogenicity. This review gathers evidence on the various roles of plasma membrane lipids in fungal virulence and how lipids might contribute to the different processes that occur during infection and treatment. Insight into the role of lipids in fungal virulence can lead to an improved understanding of the process of fungal pathogenesis and the development of new lipid-mediated therapeutic strategies. Published by Elsevier Ltd.

  19. Influence of supplemental ultraviolet-B radiation on lipid peroxidation of Chinese cabbage

    International Nuclear Information System (INIS)

    Huang Shaobai; Zhang Jingjuan; Liu Xiaozhong

    1998-01-01

    Chinese cabbage cultivar Aijiaohuang was grown in an indoor experiment treated by 0.0,130 (simulating 20% ozone depletion)kJm~(-2)day~(-1) of ultraviolet-B(UV-B) for 4 and 7 days to study the effect of supplemental UV-B radiation on flavoniods and lipid peroxidation in the leaves of Chinese cabbage. Accumulation of UV-ABSORBING flavonoids in the leaves of Chinese cabbage was induced by UV-B radiation. Enhanced UV-B radiation reduced ascorbic acid content in the leaves of Chinese cabbage. It was also found that 13.0kJm~(2)day~(-1) UV-B inhibited catalase and superoxide dismutase activities and increased malondiadehyde content in the leaves of Chinese cabbage. These effects induced by UV-B radiation was enhanced with the time course of treatment. The results above suggested that supplemental UV-B radiation enhanced lipid peroxidation of Chinese cabbage, and the accumulation of UV-absorbing flavonoid could not alleviate the damage of UV-B radiation

  20. Study on the relationship between red blood cell immunity and lipid peroxidation in patients with endometriosis

    International Nuclear Information System (INIS)

    Yang Jingxiu; Shi Shaohong; Wang Yuping; Xie Xueqin; Qin Jibao

    2005-01-01

    Objective: To assess the relationship between red blood cell immunity and lipid peroxidation (LPO) in patients with endometriosis. Methods: The percentage of positive red blood cell c3b receptor rosette (RBC c3b -RR) and red blood cell immune complex rosette (RBC-ICR) were examined in 54 patients with endometriosis and 30 controls. Serum levels of malondialdehyde (MDA), superoxidase (SOD) and glutathione peroxidase (GSH-PX) were measured by chemocolorimetry in these subjects. Results: Percentage of positive RBC-ICR and MDA levels were significantly higher in patients with endometriosis than those in controls (P c3b RR, SOD, GSH-PX, SOD/MDA ratio were significantly lower in patients with endometriosis than those in controls (P c3b -RR was negatively correlated with MDA levels (r= -0. 4428, P < 0.05) and RBC-ICRR was positively correlated with MDA(r=0.5488, P0.05). Conclusion: The lower red cell immune adhesion function was closely associated with the disturbance of metabolism of lipid peroxidation in patients with endometriosis. (authors)

  1. Interrelationships between lipid peroxidation and total antioxidant status in sedentary controls and unprofessional athletes.

    Science.gov (United States)

    Caimi, Gregorio; Canino, Baldassare; Lo Presti, Rosalia

    2010-01-01

    We examined the thiobarbituric acid-reactive substances (TBARS) as an index of lipid peroxidation, and the total antioxidant status (TAS) in 81 unprofessional athletes subdivided into three subgroups. The first group included 28 subjects who practised endurance sports, the second included 30 subjects who practised mixed sports, the third included 23 subjects who practised power sports. We enrolled also a group of 61 sedentary controls (SC). TBARS were increased and TAS was decreased in the whole group of athletes in comparison with SC; an almost similar behaviour was present also subdividing athletes according to the practised sport. A significant negative correlation between these two parameters emerged in SC but not in the whole group of athletes. Unless for the athletes that practised endurance sports a similar trend was found in athletes that practised mixed and power sports. In conclusion, at rest the symmetrical behaviour between the lipid peroxidation increase and the TAS decrease, observed in sedentary controls, was not evident in unprofessional athletes who practised different sports.

  2. Studies on cutaneous lipid peroxide with special reference to the influences of ultraviolet irradiation

    International Nuclear Information System (INIS)

    Nomura, Kazuo

    1981-01-01

    The purpose of this study was to investigate the participation of lipid peroxide (LP) in some skin damages due to ultraviolet (UV) irradiation. Results obtained were as follows. 1) Long wave UV (UVA) was irradiated to rat skin homogenates. The levels of LP increased linearly with irradiation time. 2) When 8-methoxypsoralen was added to the homogenates prior to UVA irradiation, however, the LP levels showed no increase. 3) Various anti-oxidative agents were added to homogenates and UVA was irradiated. Only Vit. E reduced the LP levels in proportion to its concentrations. 4) Anti-oxidative agents were given to rats which were then exposed to PUVA (8-methoxypsoralen plus UVA) treatment. Among them, administration of Vit. E and pantethine was associated with reduction of serum and cutaneous LP levels with only slight histologic changes in the involved skin. 5) Vit. E deficient rats were treated with PUVA. In these models, cutaneous LP levels raised from 24 hours to 96 hours after PUVA treatment and histologic changes such as vacuolization, blister formation and cell degeneration were remarkable. From the above data, it became evident that lipid peroxidation took place in skin tissue per se and even in the UVA wave length region. After PUVA treatment, cutaneous LP levels relatively well correlated with histologic changes of the involved skin. The results suggested that LP played a certain role in skin damages due to UV. (author)

  3. Reliable determination of new lipid peroxidation compounds as potential early Alzheimer Disease biomarkers.

    Science.gov (United States)

    García-Blanco, Ana; Peña-Bautista, Carmen; Oger, Camille; Vigor, Claire; Galano, Jean-Marie; Durand, Thierry; Martín-Ibáñez, Nuria; Baquero, Miguel; Vento, Máximo; Cháfer-Pericás, Consuelo

    2018-07-01

    Lipid peroxidation plays an important role in Alzheimer Disease, so corresponding metabolites found in urine samples could be potential biomarkers. The aim of this work is to develop a reliable ultra-performance liquid chromatography-tandem mass spectrometry analytical method to determine a new set of lipid peroxidation compounds in urine samples. Excellent sensitivity was achieved with limits of detection between 0.08 and 17 nmol L -1 , which renders this method suitable to monitor analytes concentrations in real samples. The method's precision was satisfactory with coefficients of variation around 5-17% (intra-day) and 8-19% (inter-day). The accuracy of the method was assessed by analysis of spiked urine samples obtaining recoveries between 70% and 120% for most of the analytes. The utility of the described method was tested by analyzing urine samples from patients early diagnosed with mild cognitive impairment or mild dementia Alzheimer Disease following the clinical standard criteria. As preliminary results, some analytes (17(RS)-10-epi-SC-Δ 15 -11-dihomo-IsoF, PGE 2 ) and total parameters (Neuroprostanes, Isoprostanes, Isofurans) show differences between the control and the clinical groups. So, these analytes could be potential early Alzheimer Disease biomarkers assessing the patients' pro-oxidant condition. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. Lipid Peroxidation, Nitric Oxide Metabolites, and Their Ratio in a Group of Subjects with Metabolic Syndrome

    Directory of Open Access Journals (Sweden)

    Gregorio Caimi

    2014-01-01

    Full Text Available Our aim was to evaluate lipid peroxidation, expressed as thiobarbituric acid-reactive substances (TBARS, nitric oxide metabolites (nitrite + nitrate expressed as NOx, and TBARS/NOx ratio in a group of subjects with metabolic syndrome (MS. In this regard we enrolled 106 subjects with MS defined according to the IDF criteria, subsequently subdivided into diabetic (DMS and nondiabetic (NDMS and also into subjects with a low triglycerides/HDL-cholesterol (TG/HDL-C index or with a high TG/HDL-C index. In the entire group and in the four subgroups of MS subjects we found an increase in TBARS and NOx levels and a decrease in TBARS/NOx ratio in comparison with normal controls. Regarding all these parameters no statistical difference between DMS and NDMS was evident, but a significant increase in NOx was present in subjects with a high TG/HDL-C index in comparison with those with a low index. In MS subjects we also found a negative correlation between TBARS/NOx ratio and TG/HDL-C index. Considering the hyperactivity of the inducible NO synthase in MS, these data confirm the altered redox and inflammatory status that characterizes the MS and suggest a link between lipid peroxidation, inflammation, and insulin resistance, evaluated as TG/HDL-C index.

  5. Lipid peroxidation analysis in salmon (Salmo salar L.) processed by e-beam

    International Nuclear Information System (INIS)

    Thomaz, Fernanda S.; Trindade, Reginaldo A.; Fanaro, Gustavo B.; Araujo, Michel M.; Villavicencio, Ana Lucia C.H.; Mancini-Filho, Jorge

    2007-01-01

    In Brazil the consumption of fish is relatively small when compared with other source of meat protein. However the diets rich in fish have association with a wide range of positive health effects, due your great deal the fat acids omega 3, EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Salmon (Salmo salar L.) specifically have those fat acids in main quantity. The omega 3 fat acids are related to the prevention of several not transmissible illness; with emphasis to cardiovascular, hypertriglyceridemia, cancer, osteoporosis and inflammatory and anti immune diseases. Food borne illnesses have been a growing concern to the governments, producers and consumers, mainly regarding the damages they cause to human health. In this context, irradiation is used as a method to preserve food. The present work aim to evaluate the lipid peroxidation in natura salmon filet irradiated on the basis of thiobarbituric acid reactive substances (TBARS). Samples were irradiated in an e beam accelerator (Radiation Dynamics Co. model JOB, New York, USA), 1,5 MeV-25mA at doses of 0, 1.0 and 2.0 kGy, analyzed 7, 15, 21, 30 e 45 days after irradiation. Irradiated samples analyzed during a 45 day period, showed a higher lipid peroxidation than the control samples at the same period, increasing with dose and storage time. However, it did not pass the permitted value. Irradiation demonstrated effective without compromising the quality of the food. (author)

  6. Lipid peroxidation in radiation pneumonitis in mouse lung and its preventation

    International Nuclear Information System (INIS)

    Kodama, Akihisa; Tsujino, Kayoko; Kono, Michio

    1998-01-01

    Lipid peroxidation of the lung in irradiated C57BL6J mice was analyzed by gas chromatography. Among six major fatty acids in the mouse lung tissue, the amounts of two unsaturated fatty acids, arachidonic acid and DHA reduced one day after irradiation, and then recovered up to the level of in the control group four weeks after irradiation. In contrast, the amounts of stearic and palmitic acid did not change significantly. The mice fed with vitamin E-enriched food showed no significant changes of fatty acids which were compatible with pathophysiological findings 4 weeks after irradiation. Reduction of both arachidonic acid and DHA following lipid peroxidation in lung tissue, was assumed to play an important role in development of radiation pneumonitis. Vitamin E seems to enable to prevent or reduce the occurrence and progression of radiation pneumonitis, but as a radical scavenger, it may also weaken the anti-tumor growth effect of low linear energy transfer (LET) irradiation as photon. (author)

  7. Lipid peroxidation analysis in salmon (Salmo salar L.) processed by e-beam

    Energy Technology Data Exchange (ETDEWEB)

    Thomaz, Fernanda S.; Trindade, Reginaldo A.; Fanaro, Gustavo B.; Araujo, Michel M.; Villavicencio, Ana Lucia C.H. [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)]. E-mail: villavic@ipen.br; Mancini-Filho, Jorge [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas]. E-mail: jmancini@usp.br

    2007-07-01

    In Brazil the consumption of fish is relatively small when compared with other source of meat protein. However the diets rich in fish have association with a wide range of positive health effects, due your great deal the fat acids omega 3, EPA (eicosapentaenoic acid) and DHA (docosahexaenoic acid). Salmon (Salmo salar L.) specifically have those fat acids in main quantity. The omega 3 fat acids are related to the prevention of several not transmissible illness; with emphasis to cardiovascular, hypertriglyceridemia, cancer, osteoporosis and inflammatory and anti immune diseases. Food borne illnesses have been a growing concern to the governments, producers and consumers, mainly regarding the damages they cause to human health. In this context, irradiation is used as a method to preserve food. The present work aim to evaluate the lipid peroxidation in natura salmon filet irradiated on the basis of thiobarbituric acid reactive substances (TBARS). Samples were irradiated in an e beam accelerator (Radiation Dynamics Co. model JOB, New York, USA), 1,5 MeV-25mA at doses of 0, 1.0 and 2.0 kGy, analyzed 7, 15, 21, 30 e 45 days after irradiation. Irradiated samples analyzed during a 45 day period, showed a higher lipid peroxidation than the control samples at the same period, increasing with dose and storage time. However, it did not pass the permitted value. Irradiation demonstrated effective without compromising the quality of the food. (author)

  8. How membrane lipids control the 3D structure and function of receptors

    OpenAIRE

    Jacques Fantini; Francisco J. Barrantes

    2018-01-01

    The cohabitation of lipids and proteins in the plasma membrane of mammalian cells is controlled by specific biochemical and biophysical rules. Lipids may be either constitutively tightly bound to cell-surface receptors (non-annular lipids) or less tightly attached to the external surface of the protein (annular lipids). The latter are exchangeable with surrounding bulk membrane lipids on a faster time scale than that of non-annular lipids. Not only do non-annular lipids bind to membrane prote...

  9. Effects of antioxidants on lipid peroxide formation in irradiated synthetic diets

    International Nuclear Information System (INIS)

    Wills, E.D.

    1980-01-01

    The effects of the antioxidants, vitamin E, propyl gallate, 2-t-butyl-4-methoxy phenol (BHA), 2,6-di-t-butyl-4-methoxy phenol (BHT), nor-dihydroguaiaretic acid (NDGA) and diphenyl-p-phenylene diamine (DPPD) in concentrations ranging between 0.001 per cent and 0.1 per cent have been tested on lipid peroxide formation in synthetic diet mixtures containing herring oil (10 per cent) mixed with starch (90 per cent) irradiated with γ-ray doses of 100 to 2000 krad. On a weight basis NDGA, DPPD, BHA and BHT were most effective and vitamin E and propyl gallate were least effective. An antioxidant concentration of 0.01 per cent normally protected against peroxide formation after a dose of 500 krad but if the dose was increased to 1000 or 2000 krad, much higher doses of antioxidant, up to 0.1 per cent, were required to give protection. Antioxidants prevented peroxide developing during post-irradiation storage even when added after irradiation. Antioxidants were partially or completely destroyed by irradiation with doses of 100 krad or more. The percentage of total antioxidant destroyed depended on the concentration; much greater destruction occurred in dilute solutions than in concentrated solutions. Vitamin E and propyl gallate were most sensitive whereas NDGA was relatively resistant. Antioxidant destruction was much enhanced if irradiation was carried out in presence of herring oil. Free radicals formed in unsaturated fatty acids of the herring oil are believed to be responsible. Lecithin and citric acid, which have been described as antioxidant synergists when added with vitamin E, caused a limited enhancement of its antioxidant action against radiation-induced peroxidation. (author)

  10. Lateral mobility of plasma membrane lipids in dividing Xenopus eggs.

    Science.gov (United States)

    Tetteroo, P A; Bluemink, J G; Dictus, W J; van Zoelen, E J; de Laat, S W

    1984-07-01

    The lateral mobility of plasma membrane lipids was analyzed during first cleavage of Xenopus laevis eggs by fluorescence photobleaching recovery (FPR) measurements, using the lipid analogs 5-(N-hexadecanoyl)aminofluorescein ("HEDAF") and 5-(N-tetradecanoyl)aminofluorescein ("TEDAF") as probes. The preexisting plasma membrane of the animal side showed an inhomogeneous, dotted fluorescence pattern after labeling and the lateral mobility of both probes used was below the detection limits of the FPR method (D much less than 10(-10) cm2/sec). In contrast, the preexisting plasma membrane of the vegetal side exhibited homogeneous fluorescence and the lateral diffusion coefficient of both probes used was relatively high (HEDAF, D = 2.8 X 10(-8) cm2/sec; TEDAF, D = 2.4 X 10(-8) cm2/sec). In the cleaving egg visible transfer of HEDAF or TEDAF from prelabeled plasma membrane to the new membrane in the furrow did not occur, even on the vegetal side. Upon labeling during cleavage, however, the new membrane was uniformly labeled and both probes were mobile, as in the vegetal preexisting plasma membrane. These data show that the membrane of the dividing Xenopus egg comprises three macrodomains: (i) the animal preexisting plasma membrane; (ii) the vegetal preexisting plasma membrane; (iii) the new furrow membrane.

  11. Peroxidation of the dried thin film of lipid by high-energy alpha particles from a cyclotron

    International Nuclear Information System (INIS)

    Agarwal, S.; Chatterjee, S.N.

    1984-01-01

    High-energy α particles produced a dose-dependent linear increase in different lipid peroxidation products (e.g., malondialdehyde (MDA), conjugated dienes, and hydroperoxides) in the dried thin film state. An inverse dose-rate effect was observed when the dose rate was varied by changing either the α-particle fluence rate or the α-particle energy. The antioxidants α-tocopherol and butylated hydroxytoluene (BHT) suppressed the α-particle-induced lipid peroxidation in the dried thin film state, and in this respect α-tocopherol was found superior to BHT. It was found that α-tocopherol was equally efficient in inhibiting lipid peroxidations by α particles and ultraviolet light

  12. The effect of deferoxamine on brain lipid peroxide levels and Na-K ATPase activity following experimental subarachnoid hemorrhage.

    Science.gov (United States)

    Bilgihan, A; Türközkan, N; Aricioğlu, A; Aykol, S; Cevik, C; Göksel, M

    1994-05-01

    1. In the present study we have studied the effects of deferoxamine treatment on lipid peroxidation and Na-K ATPase activity after experimental induction of subarachnoid haemorrhage (SAH) in guinea pigs. 2. We assessed the extent of lipid peroxidation by measuring the level of malondialdehyde and Na-K ATPase activity in 3 different groups (sham-operated, SAH, SAH + deferoxamine). 3. There was no significant difference in lipid peroxide content between sham-operated and haemorrhagic animals, but Na-K ATPase activity decreased after SAH. 4. Deferoxamine treatment reduced the malondialdehyde content and induced the recovery of Na-K ATPase activity, exerting a brain protective role against the detrimental effects of the haemorrhage.

  13. Membrane-sculpting BAR domains generate stable lipid microdomains

    DEFF Research Database (Denmark)

    Zhao, Hongxia; Michelot, Alphée; Koskela, Essi V.

    2013-01-01

    Bin-Amphiphysin-Rvs (BAR) domain proteins are central regulators of many cellular processes involving membrane dynamics. BAR domains sculpt phosphoinositide-rich membranes to generate membrane protrusions or invaginations. Here, we report that, in addition to regulating membrane geometry, BAR...... domains can generate extremely stable lipid microdomains by "freezing" phosphoinositide dynamics. This is a general feature of BAR domains, because the yeast endocytic BAR and Fes/CIP4 homology BAR (F-BAR) domains, the inverse BAR domain of Pinkbar, and the eisosomal BAR protein Lsp1 induced...... phosphoinositide clustering and halted lipid diffusion, despite differences in mechanisms of membrane interactions. Lsp1 displays comparable low diffusion rates in vitro and in vivo, suggesting that BAR domain proteins also generate stable phosphoinositide microdomains in cells. These results uncover a conserved...

  14. Lipid Acrobatics in the Membrane Fusion Arena

    NARCIS (Netherlands)

    Markvoort, Albert J.; Marrink, Siewert J.; Chernomordik, Leonid V.; Kozlov, Michael M.

    2011-01-01

    In this review, we describe the recent contribution of computer simulation approaches to unravel the molecular details of membrane fusion. Over the past decade, fusion between apposed membranes and vesicles has been studied using a large variety of simulation methods and systems. Despite the variety

  15. Lipid Directed Intrinsic Membrane Protein Segregation

    DEFF Research Database (Denmark)

    Hansen, Jesper S.; Thompson, James R.; Helix Nielsen, Claus

    2013-01-01

    We demonstrate a new approach for direct reconstitution of membrane proteins during giant vesicle formation. We show that it is straightforward to create a tissue-like giant vesicle film swelled with membrane protein using aquaporin SoPIP2;1 as an illustration. These vesicles can also be easily h...

  16. Digital holographic microscopy of phase separation in multicomponent lipid membranes

    Science.gov (United States)

    Farzam Rad, Vahideh; Moradi, Ali-Reza; Darudi, Ahmad; Tayebi, Lobat

    2016-12-01

    Lateral in-homogeneities in lipid compositions cause microdomains formation and change in the physical properties of biological membranes. With the presence of cholesterol and mixed species of lipids, phospholipid membranes segregate into lateral domains of liquid-ordered and liquid-disordered phases. Coupling of two-dimensional intralayer phase separations and interlayer liquid-crystalline ordering in multicomponent membranes has been previously demonstrated. By the use of digital holographic microscopy (DHMicroscopy), we quantitatively analyzed the volumetric dynamical behavior of such membranes. The specimens are lipid mixtures composed of sphingomyelin, cholesterol, and unsaturated phospholipid, 1,2-dioleoyl-sn-glycero-3-phosphocholine. DHMicroscopy in a transmission mode is an effective tool for quantitative visualization of phase objects. By deriving the associated phase changes, three-dimensional information on the morphology variation of lipid stacks at arbitrary time scales is obtained. Moreover, the thickness distribution of the object at demanded axial planes can be obtained by numerical focusing. Our results show that the volume evolution of lipid domains follows approximately the same universal growth law of previously reported area evolution. However, the thickness of the domains does not alter significantly by time; therefore, the volume evolution is mostly attributed to the changes in area dynamics. These results might be useful in the field of membrane-based functional materials.

  17. Inducing morphological changes in lipid bilayer membranes with microfabricated substrates

    Science.gov (United States)

    Liu, Fangjie; Collins, Liam F.; Ashkar, Rana; Heberle, Frederick A.; Srijanto, Bernadeta R.; Collier, C. Patrick

    2016-11-01

    Lateral organization of lipids and proteins into distinct domains and anchoring to a cytoskeleton are two important strategies employed by biological membranes to carry out many cellular functions. However, these interactions are difficult to emulate with model systems. Here we use the physical architecture of substrates consisting of arrays of micropillars to systematically control the behavior of supported lipid bilayers - an important step in engineering model lipid membrane systems with well-defined functionalities. Competition between attractive interactions of supported lipid bilayers with the underlying substrate versus the energy cost associated with membrane bending at pillar edges can be systematically investigated as functions of pillar height and pitch, chemical functionalization of the microstructured substrate, and the type of unilamellar vesicles used for assembling the supported bilayer. Confocal fluorescent imaging and AFM measurements highlight correlations that exist between topological and mechanical properties of lipid bilayers and lateral lipid mobility in these confined environments. This study provides a baseline for future investigations into lipid domain reorganization on structured solid surfaces and scaffolds for cell growth.

  18. Lipid nanotechnologies for structural studies of membrane-associated proteins.

    Science.gov (United States)

    Stoilova-McPhie, Svetla; Grushin, Kirill; Dalm, Daniela; Miller, Jaimy

    2014-11-01

    We present a methodology of lipid nanotubes (LNT) and nanodisks technologies optimized in our laboratory for structural studies of membrane-associated proteins at close to physiological conditions. The application of these lipid nanotechnologies for structure determination by cryo-electron microscopy (cryo-EM) is fundamental for understanding and modulating their function. The LNTs in our studies are single bilayer galactosylceramide based nanotubes of ∼20 nm inner diameter and a few microns in length, that self-assemble in aqueous solutions. The lipid nanodisks (NDs) are self-assembled discoid lipid bilayers of ∼10 nm diameter, which are stabilized in aqueous solutions by a belt of amphipathic helical scaffold proteins. By combining LNT and ND technologies, we can examine structurally how the membrane curvature and lipid composition modulates the function of the membrane-associated proteins. As proof of principle, we have engineered these lipid nanotechnologies to mimic the activated platelet's phosphtaidylserine rich membrane and have successfully assembled functional membrane-bound coagulation factor VIII in vitro for structure determination by cryo-EM. The macromolecular organization of the proteins bound to ND and LNT are further defined by fitting the known atomic structures within the calculated three-dimensional maps. The combination of LNT and ND technologies offers a means to control the design and assembly of a wide range of functional membrane-associated proteins and complexes for structural studies by cryo-EM. The presented results confirm the suitability of the developed methodology for studying the functional structure of membrane-associated proteins, such as the coagulation factors, at a close to physiological environment. © 2014 Wiley Periodicals, Inc.

  19. Effect of Membrane Tension on the Electric Field and Dipole Potential of Lipid Bilayer Membrane

    Science.gov (United States)

    Warshaviak, Dora Toledo; Muellner, Michael J.; Chachisvilis, Mirianas

    2011-01-01

    The dipole potential of lipid bilayer membrane controls the difference in permeability of the membrane to oppositely charged ions. We have combined molecular dynamics (MD) simulations and experimental studies to determine changes in electric field and electrostatic potential of 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) lipid bilayer in response to applied membrane tension. MD simulations based on CHARMM36 force field showed that electrostatic potential of DOPC bilayer decreases by ~45 mV in the physiologically relevant range of membrane tension values (0 to 15 dyn/cm). The electrostatic field exhibits a peak (~0.8×109 V/m) near the water/lipid interface which shifts by 0.9 Å towards the bilayer center at 15 dyn/cm. Maximum membrane tension of 15 dyn/cm caused 6.4% increase in area per lipid, 4.7% decrease in bilayer thickness and 1.4% increase in the volume of the bilayer. Dipole-potential sensitive fluorescent probes were used to detect membrane tension induced changes in DOPC vesicles exposed to osmotic stress. Experiments confirmed that dipole potential of DOPC bilayer decreases at higher membrane tensions. These results are suggestive of a potentially new mechanosensing mechanism by which mechanically induced structural changes in the lipid bilayer membrane could modulate the function of membrane proteins by altering electrostatic interactions and energetics of protein conformational states. PMID:21722624

  20. Influence Of Pentoxifylline And Mexidol On Lipid Peroxidation And Anti-oxidant System In Patients With Urolithiasis

    Directory of Open Access Journals (Sweden)

    A.B. Polozov

    2009-12-01

    Full Text Available Research objective is to prove correction possibility of lipid peroxidation and antioxidant system protection in neph-rolithiasis by taking pentoxifylline and mexidol. 158 patients with kidney concretion have been under the research. Distance shock-wave lithotripsy (ESWL has been carried out. Structure of stones and antioxidant system state have been investigated in all patients. They have been divided into three groups - control, receiving pentoxifylline and receiving mexidol. Influence of indicated preparations on processes of lipid peroxidation and antioxidant system has been studied in case of different structure of concretion

  1. Membrane-Sculpting BAR Domains Generate Stable Lipid Microdomains

    Science.gov (United States)

    Zhao, Hongxia; Michelot, Alphée; Koskela, Essi V.; Tkach, Vadym; Stamou, Dimitrios; Drubin, David G.; Lappalainen, Pekka

    2014-01-01

    SUMMARY Bin-Amphiphysin-Rvs (BAR) domain proteins are central regulators of many cellular processes involving membrane dynamics. BAR domains sculpt phosphoinositide-rich membranes to generate membrane protrusions or invaginations. Here, we report that, in addition to regulating membrane geometry, BAR domains can generate extremely stable lipid microdomains by “freezing” phosphoinositide dynamics. This is a general feature of BAR domains, because the yeast endocytic BAR and Fes/CIP4 homology BAR (F-BAR) domains, the inverse BAR domain of Pinkbar, and the eisosomal BAR protein Lsp1 induced phosphoinositide clustering and halted lipid diffusion, despite differences in mechanisms of membrane interactions. Lsp1 displays comparable low diffusion rates in vitro and in vivo, suggesting that BAR domain proteins also generate stable phosphoinositide microdomains in cells. These results uncover a conserved role for BAR superfamily proteins in regulating lipid dynamics within membranes. Stable microdomains induced by BAR domain scaffolds and specific lipids can generate phase boundaries and diffusion barriers, which may have profound impacts on diverse cellular processes. PMID:24055060

  2. Comparative analysis of changes in protein and lipid metabolism, lipid peroxidation, and hemostasis under the effects of polychlorinated dibenzo-p-dioxins and radiation

    International Nuclear Information System (INIS)

    Kuntsevich, A.D.; Baulin, S.I.; Golovkov, V.F.; Rembovskii, V.R.; Smirnova, L.A.; Troshkin, N.M.

    1994-01-01

    Polychlorinated dibenzo-p-dioxins (PCDD) and ionizing radiation are among the most hazardous environmental factors causing ecological catastrophes and mass afflications in various accidents involving nuclear power plants and chemical industrial enterprises. The authors previously established that the simultaneous action of a toxic dose of PCDD and ionizing radiation increases the combined toxic effect. The effects of these chemical and physical factors were superadditive (the biological potentiation effect). Here, the authors compare the effects of PCDD and irradiation on protein and lipid metabolism, lipid peroxidation, and hemostasis in order to learn more about biochemical mechanisms mediating the potentiation effect. The experimental evidence suggests that PCDD can modify the biological effects of ionizing radiation through the generation of free radicals and activation of the chain reactions of free-radical lipid peroxidation, such as the formation of peroxides or malonic dialdehyde. The toxic effects of PCDD and ionizing radiation are based on free-radical reactions and chemical pathology. In other words, the chemical and physical factors directly and selectively hit the same biological target, thereby increasing their combined toxic effects. The results can partially explain the observed potentiating effect of the combined action of ionizing radiation and PCDD on the body. This phenomenon is based on biochemical processes generating an abundance of products of lipid peroxidation and the decrease in the body's defenses caused by disorders in protein and lipid metabolism and blood coagulation

  3. DNA release from lipoplexes by anionic lipids: correlation with lipid mesomorphism, interfacial curvature, and membrane fusion

    Energy Technology Data Exchange (ETDEWEB)

    Tarahovsky, Yury S.; Koynova, Rumiana; MacDonald, Robert C. (Northwestern)

    2010-01-18

    DNA release from lipoplexes is an essential step during lipofection and is probably a result of charge neutralization by cellular anionic lipids. As a model system to test this possibility, fluorescence resonance energy transfer between DNA and lipid covalently labeled with Cy3 and BODIPY, respectively, was used to monitor the release of DNA from lipid surfaces induced by anionic liposomes. The separation of DNA from lipid measured this way was considerably slower and less complete than that estimated with noncovalently labeled DNA, and depends on the lipid composition of both lipoplexes and anionic liposomes. This result was confirmed by centrifugal separation of released DNA and lipid. X-ray diffraction revealed a clear correlation of the DNA release capacity of the anionic lipids with the interfacial curvature of the mesomorphic structures developed when the anionic and cationic liposomes were mixed. DNA release also correlated with the rate of fusion of anionic liposomes with lipoplexes. It is concluded that the tendency to fuse and the phase preference of the mixed lipid membranes are key factors for the rate and extent of DNA release. The approach presented emphasizes the importance of the lipid composition of both lipoplexes and target membranes and suggests optimal transfection may be obtained by tailoring lipoplex composition to the lipid composition of target cells.

  4. Pressure effects on lipids and bio-membrane assemblies

    Directory of Open Access Journals (Sweden)

    Nicholas J. Brooks

    2014-11-01

    Full Text Available Membranes are amongst the most important biological structures; they maintain the fundamental integrity of cells, compartmentalize regions within them and play an active role in a wide range of cellular processes. Pressure can play a key role in probing the structure and dynamics of membrane assemblies, and is also critical to the biology and adaptation of deep-sea organisms. This article presents an overview of the effect of pressure on the mesostructure of lipid membranes, bilayer organization and lipid–protein assemblies. It also summarizes recent developments in high-pressure structural instrumentation suitable for experiments on membranes.

  5. Plant lipid environment and membrane enzymes: the case of the plasma membrane H+-ATPase.

    Science.gov (United States)

    Morales-Cedillo, Francisco; González-Solís, Ariadna; Gutiérrez-Angoa, Lizbeth; Cano-Ramírez, Dora Luz; Gavilanes-Ruiz, Marina

    2015-04-01

    Several lipid classes constitute the universal matrix of the biological membranes. With their amphipathic nature, lipids not only build the continuous barrier that confers identity to every cell and organelle, but they are also active actors that modulate the activity of the proteins immersed in the lipid bilayer. The plasma membrane H(+)-ATPase, an enzyme from plant cells, is an excellent example of a transmembrane protein whose activity is influenced by the hydrophilic compartments at both sides of the membrane and by the hydrophobic domains of the lipid bilayer. As a result, an extensive documentation of the effect of numerous amphiphiles in the enzyme activity can be found. Detergents, membrane glycerolipids, and sterols can produce activation or inhibition of the enzyme activity. In some cases, these effects are associated with the lipids of the membrane bulk, but in others, a direct interaction of the lipid with the protein is involved. This review gives an account of reports related to the action of the membrane lipids on the H(+)-ATPase activity.

  6. Effect of Flavonoids on Glutathione Level, Lipid Peroxidation and Cytochrome P450 CYP1A1 Expression in Human Laryngeal Carcinoma Cell Lines

    Directory of Open Access Journals (Sweden)

    Lidija Vuković

    2007-01-01

    Full Text Available Flavonoids are phytochemicals exhibiting a wide range of biological activities, among which are antioxidant activity, the ability to modulate activity of several enzymes or cell receptors and possibility to interfere with essential biochemical pathways. Using human laryngeal carcinoma HEp2 cells and their drug-resistant CK2 subline, we examined the effect of five flavonoids, three structurally related flavons (quercetin, fisetin, and myricetin, one flavonol (luteolin and one glycosilated flavanone (naringin for: (i their ability to inhibit mitochondrial dehydrogenases as an indicator of cytotoxic effect, (ii their influence on glutathione level, (iii antioxidant/prooxidant effects and influence on cell membrane permeability, and (iv effect on expression of cytochrome CYP1A1. Cytotoxic action of the investigated flavonoids after 72 hours of treatment follows this order: luteolin>quercetin>fisetin>naringin>myricetin. Our results show that CK2 were more resistant to toxic concentrations of flavonoids as compared to parental cells. Quercetin increased the total GSH level in both cell lines. CK2 cells are less perceptible to lipid peroxidation and damage caused by free radicals. Quercetin showed prooxidant effect in both cell lines, luteolin only in HEp2 cells, whereas other tested flavonoids did not cause lipid peroxidation in the tested cell lines. These data suggest that the same compound, quercetin, can act as a prooxidant, but also, it may prevent damage in cells caused by free radicals, due to the induction of GSH, by forming less harmful complex. Quercetin treatment damaged cell membranes in both cell lines. Fisetin caused higher cell membrane permeability only in HEp2 cells. However, these two compounds did not enhance the damage caused by hydrogen peroxide. Quercetin, naringin, myricetin and fisetin increased the expression of CYP1A1 in both cell lines, while luteolin decreased basal level of CYP1A1 only in HEp2 cells. In conclusion, small

  7. Hydration dynamics of a lipid membrane: Hydrogen bond networks and lipid-lipid associations

    Science.gov (United States)

    Srivastava, Abhinav; Debnath, Ananya

    2018-03-01

    reveal that the slow relaxation rates of interfacial waters in the vicinity of lipids are originated from the chemical confinement of concerted hydrogen bond networks. The analysis suggests that the networks in the hydration layer of membranes dynamically facilitate the water mediated lipid-lipid associations which can provide insights on the thermodynamic stability of soft interfaces relevant to biological systems in the future.

  8. Phosphoinositides, Major Actors in Membrane Trafficking and Lipid Signaling Pathways

    Directory of Open Access Journals (Sweden)

    Johan-Owen De Craene

    2017-03-01

    Full Text Available Phosphoinositides are lipids involved in the vesicular transport of proteins and lipids between the different compartments of eukaryotic cells. They act by recruiting and/or activating effector proteins and thus are involved in regulating various cellular functions, such as vesicular budding, membrane fusion and cytoskeleton dynamics. Although detected in small concentrations in membranes, their role is essential to cell function, since imbalance in their concentrations is a hallmark of many cancers. Their synthesis involves phosphorylating/dephosphorylating positions D3, D4 and/or D5 of their inositol ring by specific lipid kinases and phosphatases. This process is tightly regulated and specific to the different intracellular membranes. Most enzymes involved in phosphoinositide synthesis are conserved between yeast and human, and their loss of function leads to severe diseases (cancer, myopathy, neuropathy and ciliopathy.

  9. Tethered and Polymer Supported Bilayer Lipid Membranes: Structure and Function

    Directory of Open Access Journals (Sweden)

    Jakob Andersson

    2016-05-01

    Full Text Available Solid supported bilayer lipid membranes are model systems to mimic natural cell membranes in order to understand structural and functional properties of such systems. The use of a model system allows for the use of a wide variety of analytical tools including atomic force microscopy, impedance spectroscopy, neutron reflectometry, and surface plasmon resonance spectroscopy. Among the large number of different types of model membranes polymer-supported and tethered lipid bilayers have been shown to be versatile and useful systems. Both systems consist of a lipid bilayer, which is de-coupled from an underlying support by a spacer cushion. Both systems will be reviewed, with an emphasis on the effect that the spacer moiety has on the bilayer properties.

  10. Probing protein-lipid interactions by FRET between membrane fluorophores

    Science.gov (United States)

    Trusova, Valeriya M.; Gorbenko, Galyna P.; Deligeorgiev, Todor; Gadjev, Nikolai

    2016-09-01

    Förster resonance energy transfer (FRET) is a powerful fluorescence technique that has found numerous applications in medicine and biology. One area where FRET proved to be especially informative involves the intermolecular interactions in biological membranes. The present study was focused on developing and verifying a Monte-Carlo approach to analyzing the results of FRET between the membrane-bound fluorophores. This approach was employed to quantify FRET from benzanthrone dye ABM to squaraine dye SQ-1 in the model protein-lipid system containing a polycationic globular protein lysozyme and negatively charged lipid vesicles composed of phosphatidylcholine and phosphatidylglycerol. It was found that acceptor redistribution between the lipid bilayer and protein binding sites resulted in the decrease of FRET efficiency. Quantification of this effect in terms of the proposed methodology yielded both structural and binding parameters of lysozyme-lipid complexes.

  11. Selective Interaction of a Cationic Polyfluorene with Model Lipid Membranes: Anionic versus Zwitterionic Lipids

    Directory of Open Access Journals (Sweden)

    Zehra Kahveci

    2014-03-01

    Full Text Available This paper explores the interaction mechanism between the conjugated polyelectrolyte {[9,9-bis(6'-N,N,N-trimethylammoniumhexyl]fluorene-phenylene}bromide (HTMA-PFP and model lipid membranes. The study was carried out using different biophysical techniques, mainly fluorescence spectroscopy and microscopy. Results show that despite the preferential interaction of HTMA-PFP with anionic lipids, HTMA-PFP shows affinity for zwitterionic lipids; although the interaction mechanism is different as well as HTMA-PFP’s final membrane location. Whilst the polyelectrolyte is embedded within the lipid bilayer in the anionic membrane, it remains close to the surface, forming aggregates that are sensitive to the physical state of the lipid bilayer in the zwitterionic system. The different interaction mechanism is reflected in the polyelectrolyte fluorescence spectrum, since the maximum shifts to longer wavelengths in the zwitterionic system. The intrinsic fluorescence of HTMA-PFP was used to visualize the interaction between polymer and vesicles via fluorescence microscopy, thanks to its high quantum yield and photostability. This technique allows the selectivity of the polyelectrolyte and higher affinity for anionic membranes to be observed. The results confirmed the appropriateness of using HTMA-PFP as a membrane fluorescent marker and suggest that, given its different behaviour towards anionic and zwitterionic membranes, HTMA-PFP could be used for selective recognition and imaging of bacteria over mammalian cells.

  12. Effects of Dietary Lycopene Supplementation on Plasma Lipid Profile, Lipid Peroxidation and Antioxidant Defense System in Feedlot Bamei Lamb

    Directory of Open Access Journals (Sweden)

    Hongqin Jiang

    2015-07-01

    Full Text Available Lycopene, a red non-provitamin A carotenoid, mainly presenting in tomato and tomato byproducts, has the highest antioxidant activity among carotenoids because of its high number of conjugated double bonds. The objective of this study was to investigate the effect of lycopene supplementation in the diet on plasma lipid profile, lipid peroxidation and antioxidant defense system in feedlot lamb. Twenty-eight Bamei male lambs (90 days old were divided into four groups and fed a basal diet (LP0, 40:60 roughage: concentrate or the basal diet supplemented with 50, 100, and 200 mg/kg lycopene. After 120 days of feeding, all lambs were slaughtered and sampled. Dietary lycopene supplementation significantly reduced the levels of plasma total cholesterol (p0.05. The levels of TG (p<0.001 and LDL-C (p<0.001 were decreased with the feeding time extension, and both showed a linear trend (p<0.01. Malondialdehyde level in plasma and liver decreased linearly with the increase of lycopene inclusion levels (p<0.01. Dietary lycopene intake linearly increased the plasma antioxidant vitamin E level (p<0.001, total antioxidant capacity (T-AOC, p<0.05, and activities of catalase (CAT, p<0.01, glutathione peroxidase (GSH-Px, p<0.05 and superoxide dismutase (SOD, p<0.05. The plasma T-AOC and activities of GSH-Px and SOD decreased with the extension of the feeding time. In liver, dietary lycopene inclusion showed similar antioxidant effects with respect to activities of CAT (p<0.05, linearly and SOD (p<0.001, linearly. Therefore, it was concluded that lycopene supplementation improved the antioxidant status of the lamb and optimized the plasma lipid profile, the dosage of 200 mg lycopene/kg feed might be desirable for growing lambs to prevent environment stress and maintain normal physiological metabolism.

  13. Evaluation of lipid peroxidation activity at intravenous administration of gold nanorods in rats with simulated diabetes and transplanted liver cancer

    Science.gov (United States)

    Bucharskaya, Alla B.; Dikht, Natalia I.; Afanasyeva, Galina A.; Terentyuk, Georgy S.; Maslyakova, Galina N.; Zaraeva, Nadezhda V.; Khlebtsov, Nikolai G.; Khlebtsov, Boris N.

    2014-01-01

    In the experiment the white outbred rats with transplanted liver cancer (cholangiocarcinoma line PC-1) and simulated alloxan diabetes were treated by single intravenous injection of gold nanorods. State of lipid peroxidation was evaluated by the following parameters: the malondialdehyde, lipid hydroperoxide, the average weght molecules in the serum of animals by conventional spectrophotometric methods study using a spectrofluorometer RF-5301 PC (Shimadzu, Japan). In both experimental groups of animals the significant increasing of levels of lipid peroxidation products was noted compared with control group. After intravenous administration of nanoparticles in the group of animals with alloxan diabetes the activation of a free radical oxidation was not observed, in group with transplanted liver cancer the increasing of levels of lipid hydroperoxide, malondialdehyde was established.

  14. Lipid reorganization induced by Shiga toxin clustering on planar membranes.

    Directory of Open Access Journals (Sweden)

    Barbara Windschiegl

    Full Text Available The homopentameric B-subunit of bacterial protein Shiga toxin (STxB binds to the glycolipid Gb(3 in plasma membranes, which is the initial step for entering cells by a clathrin-independent mechanism. It has been suggested that protein clustering and lipid reorganization determine toxin uptake into cells. Here, we elucidated the molecular requirements for STxB induced Gb(3 clustering and for the proposed lipid reorganization in planar membranes. The influence of binding site III of the B-subunit as well as the Gb(3 lipid structure was investigated by means of high resolution methods such as fluorescence and scanning force microscopy. STxB was found to form protein clusters on homogenous 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC/cholesterol/Gb(3 (65:30:5 bilayers. In contrast, membranes composed of DOPC/cholesterol/sphingomyelin/Gb(3 (40:35:20:5 phase separate into a liquid ordered and liquid disordered phase. Dependent on the fatty acid composition of Gb(3, STxB-Gb(3 complexes organize within the liquid ordered phase upon protein binding. Our findings suggest that STxB is capable of forming a new membrane phase that is characterized by lipid compaction. The significance of this finding is discussed in the context of Shiga toxin-induced formation of endocytic membrane invaginations.

  15. Simulation of water transport through a lipid membrane

    Energy Technology Data Exchange (ETDEWEB)

    Marrink, S.J.; Berendsen, H.J.C. (Univ. of Groningen (Netherlands))

    1994-04-14

    To obtain insight in the process of water permeation through a lipid membrane we performed molecular dynamics simulations on a phospholipid (DPPC)/water system with atomic detail. Since the actual process of permeation is too slow to be studied directly, we deduced the permeation rate indirectly via computation of the free energy and diffusion rate profiles of a water molecule across the bilayer. We concluded that the permeation of water through a lipid membrane cannot be described adequately by a simple homogeneous solubility-diffusion model. Both the excess free energy and the diffusion rate strongly depend on the position in the membrane, as a result from the inhomogeneous nature of the membrane. The calculated excess free energy profile has a shallow slope and a maximum height of 26 kJ/mol. The diffusion rate is highest in the middle of the membrane where the lipid density is low. In the interfacial region almost all water molecules are bound by the lipid headgroups, and the diffusion turns out to be 1 order of magnitude smaller. The total transport process is essentially determined by the free energy barrier. 78 refs., 12 figs.

  16. Watching individual molecules flex within lipid membranes using SERS

    Science.gov (United States)

    Taylor, Richard W.; Benz, Felix; Sigle, Daniel O.; Bowman, Richard W.; Bao, Peng; Roth, Johannes S.; Heath, George R.; Evans, Stephen D.; Baumberg, Jeremy J.

    2014-08-01

    Interrogating individual molecules within bio-membranes is key to deepening our understanding of biological processes essential for life. Using Raman spectroscopy to map molecular vibrations is ideal to non-destructively `fingerprint' biomolecules for dynamic information on their molecular structure, composition and conformation. Such tag-free tracking of molecules within lipid bio-membranes can directly connect structure and function. In this paper, stable co-assembly with gold nano-components in a `nanoparticle-on-mirror' geometry strongly enhances the local optical field and reduces the volume probed to a few nm3, enabling repeated measurements for many tens of minutes on the same molecules. The intense gap plasmons are assembled around model bio-membranes providing molecular identification of the diffusing lipids. Our experiments clearly evidence measurement of individual lipids flexing through telltale rapid correlated vibrational shifts and intensity fluctuations in the Raman spectrum. These track molecules that undergo bending and conformational changes within the probe volume, through their interactions with the environment. This technique allows for in situ high-speed single-molecule investigations of the molecules embedded within lipid bio-membranes. It thus offers a new way to investigate the hidden dynamics of cell membranes important to a myriad of life processes.

  17. Acrolein, A Reactive Product of Lipid Peroxidation, Induces Oxidative Modification of Cytochrome c

    Energy Technology Data Exchange (ETDEWEB)

    Kang, Jung Hoon [Cheongju Univ., Cheongju (Korea, Republic of)

    2013-11-15

    Acrolein (ACR) is a well-known carbonyl toxin produced by lipid peroxidation of polyunsaturated fatty acids, which is involved in the pathogenesis of neurodegenerative disorders such as Alzheimer's disease (AD). In Alzheimer's brain, ACR was found to be elevated in hippocampus and temporal cortex where oxidative stress is high. In this study, we evaluated oxidative modification of cytochrome c occurring after incubation with ACR. When cytochrome c was incubated with ACR, protein aggregation increased in a dose-dependent manner. The formation of carbonyl compounds and the release of iron were obtained in ACR-treated cytochrome c. Reactive oxygen species scavengers and iron specific chelator inhibited the ACR-mediated cytochrome c modification and carbonyl compound formation. Our data demonstrate that oxidative damage of cytochrome c by ACR might induce disruption of cyotochrome c structure and iron mishandling as a contributing factor to the pathology of AD.

  18. Acrolein, A Reactive Product of Lipid Peroxidation, Induces Oxidative Modification of Cytochrome c

    International Nuclear Information System (INIS)

    Kang, Jung Hoon

    2013-01-01

    Acrolein (ACR) is a well-known carbonyl toxin produced by lipid peroxidation of polyunsaturated fatty acids, which is involved in the pathogenesis of neurodegenerative disorders such as Alzheimer's disease (AD). In Alzheimer's brain, ACR was found to be elevated in hippocampus and temporal cortex where oxidative stress is high. In this study, we evaluated oxidative modification of cytochrome c occurring after incubation with ACR. When cytochrome c was incubated with ACR, protein aggregation increased in a dose-dependent manner. The formation of carbonyl compounds and the release of iron were obtained in ACR-treated cytochrome c. Reactive oxygen species scavengers and iron specific chelator inhibited the ACR-mediated cytochrome c modification and carbonyl compound formation. Our data demonstrate that oxidative damage of cytochrome c by ACR might induce disruption of cyotochrome c structure and iron mishandling as a contributing factor to the pathology of AD

  19. Protective effects of nelumbo nucifera against {gamma}-irradiation-induced lipid peroxidation in mice urine

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Il Yun; Park, Yong Dae; Jin, Caang Hyun; Choi, Dae Seong [Korea Atomic Energy Research Institute, Jeongeup (Korea, Republic of); Lee, Hyo Jung [Gwangju Institute of Science and Technology, Gwangju (Korea, Republic of)

    2009-12-15

    The radioprotective effect of isoquercitrin-abundant fraction (IAF) of N. nucifera Gaertn. Ieaf extract against {gamma}-irradiation-induced oxidative stress was evaluated by the lipid peroxidation-derived aldehydes (LPDAs) as a marker for oxidative risk in mice urine, and the DNA damage using comet assay in RAW 264.7 cells. Mice that were treated with IAF (50 mg/kg) and {gamma}-irradiation showed considerably decreased LPDA levels relative to those that had received {gamma}-irradiation alone. Furthermore, pretreatment with IAF resulted in a significant decrease in the amount of DNA damage in cells. It is demonstrated that pretreatment with IAF of N. nucifera Gaertn. gives protection against irradiation-induced cellular damage.

  20. Role of Serum Iron in the Activation of Lipid Peroxidation in Critical Conditions

    Directory of Open Access Journals (Sweden)

    Yu. P. Orlov

    2006-01-01

    Full Text Available Twenty-four critically ill patients due to generalized purulent peritonitis, pancreatonecrosis, thermal skin injuries, and severe poisoning by acetic acid were examined. The general regularities of the effect of high serum iron concentrations on the health status of patients, on the activity of antioxidative enzymes, and on the initiation of lipid peroxidation (LPO processes, as supported by the values of Fe2+-induced chemiluminescence, were revealed. In critically ill patients, iron metabolism occurs with the overload of a transport protein, such as transferrin, which is caused by intravascular hemolysis and hemoglobin metabolism to ionized iron. The overload of proteins responsible for iron transport leads to the tissue accumulation of free (ferrous and ferric iron that is actively involved in the processes of LPO initiation with excess synthesis of cytotoxic radicals, which in turn accounts for the severity of endotoxicosis.

  1. Lipid peroxidation in neonatal mouse brain subjected to two different types of hypoxia.

    Science.gov (United States)

    Hasegawa, K; Yoshioka, H; Sawada, T; Nishikawa, H

    1991-01-01

    To elucidate the role of free radicals in the pathogenesis of neonatal hypoxic encephalopathy, we determined the content of thiobarbituric acid reactants (TBARs), as an index of lipid peroxidation related with a free radical reaction, in the brains of newborn mice during hypoxia and recovery from hypoxia. Hypoxic stress was induced by 100% nitrogen gas breathing (N2 group) or 100% carbon dioxide gas breathing (CO2 group). TBARs increased with 20 minutes of hypoxia and returned to the control level during the recovery period in both groups. The increase in TBARs in the CO2 group was greater than that in the N2 group. These results may suggest that free radical reaction occurs during the hypoxic period and that CO2 hypoxia is more effective on free radical production in the newborn brain than N2 hypoxia.

  2. Altered Antioxidant Status and Increased Lipid Per-Oxidation in Seminal Plasma of Tunisian Infertile Men

    Science.gov (United States)

    Atig, Fatma; Raffa, Monia; Ali, Habib Ben; Abdelhamid, Kerkeni; Saad, Ali; Ajina, Mounir

    2012-01-01

    Human seminal plasma is a natural reservoir of antioxidants that protect spermatozoa from oxidative damages. There is evidence in literature supports the fact that impairments in seminal antioxidant and lipid per-oxidation status play important roles in the physiopathology of male infertility. Our present study forms the first one which was carried out in Tunisia. We evaluated the antioxidant status in the seminal plasma of 120 infertile men programmed to In Vitro Fertilization (IVF) for the first tentative. Patients were characterized by an idiopathic infertility. They were divided into three groups: normozoospermics who were considered as controls (n=40), asthenozoospermics (Astheno; n=45) and oligoasthenoteratozoospermics (OAT; n=35). Seminal activities of superoxide dismutase (SOD) and glutathione peroxidase (GPX) and the levels of glutathione (GSH), zinc (Zn) and malondialdehyde (MDA) were measured. With the significant increase of the seminal activities of SOD and GPX in normozoospermics group, there were positive correlations observed between this enzymes and sperm quality. Also, significant elevated rates of seminal zinc and GSH were observed in control group, but there was contradictory associations reflecting the effects of these antioxidants on semen parameters. However, we noted significant increase of MDA levels in groups with abnormal seminogram. We showed negative associations between this per-oxidative marker and sperm parameters. These results obviously suggested that impairment on seminal antioxidants is an important risk factor for low sperm quality associated to idiopathic infertility and as a result can lead to poor IVF outcome. PMID:22211112

  3. Lipid peroxidation and antioxidant enzymes activity in Plasmodium vivax malaria patients evolving with cholestatic jaundice

    Science.gov (United States)

    2013-01-01

    Background Plasmodium vivax infection has been considered a benign and self-limiting disease, however, recent studies highlight the association between vivax malaria and life-threatening manifestations. Increase in reactive oxygen species has already been described in vivax malaria, as a result of the increased metabolic rate triggered by the multiplying parasite, and large quantities of toxic redox-active byproducts generated. The present study aimed to study the oxidative stress responses in patients infected with P. vivax, who developed jaundice (hyperbilirubinaemia) in the course of the disease, a common clinical complication related to this species. Methods An evaluation of the lipid peroxidation and antioxidant enzymes profile was performed in 28 healthy individuals and compared with P. vivax infected patients with jaundice, i.e., bilirubin jaundice (34 patients), on day 1 (D1) and day 14 (D14) after anti-malarial therapy. Results Hyperbilirubinaemia was more frequent among women and patients experiencing their first malarial infection, and lower haemoglobin and higher lactate dehydrogenase levels were observed in this group. Malondialdehyde levels and activity of celuroplasmin and glutathione reductase were increased in the plasma from patients with P. vivax with jaundice compared to the control group on D1. However, the activity of thioredoxin reductase was decreased. The enzymes glutathione reductase, thioredoxin reductase, thiols and malondialdehyde also differed between jaundiced versus non-jaundiced patients. On D14 jaundice and parasitaemia had resolved and oxidative stress biomarkers were very similar to the control group. Conclusion Cholestatic hyperbilirubinaemia in vivax malaria cannot be totally disassociated from malaria-related haemolysis. However, significant increase of lipid peroxidation markers and changes in antioxidant enzymes in patients with P. vivax-related jaundice was observed. These results suggest oxidative processes contributing

  4. Assessment of semen function and lipid peroxidation among lead exposed men

    International Nuclear Information System (INIS)

    Kasperczyk, Aleksandra; Kasperczyk, Slawomir; Horak, Stanislaw; Ostalowska, Alina; Grucka-Mamczar, Ewa; Romuk, Ewa; Olejek, Anita; Birkner, Ewa

    2008-01-01

    The study population included healthy, fertile men, employees of Zinc and Lead Metalworks (n = 63). Workers exposed to lead were divided into two groups: a group with moderate exposure to lead (ME) - blood lead level (PbB) 25-40 μg/dl and a group with high exposure to lead (HE) PbB = 40-81 μg/dl. The control group consisted of office workers with no history of occupational exposure to lead. Evaluation of lead, cadmium and zinc level in blood and seminal plasma, zinc protoporphyrin in blood (ZPP), 5-aminolevulinic acid in urine (ALA), malondialdehyde (MDA) in seminal plasma and sperm analysis were performed. No differences were noted in the concentration of cadmium and zinc in blood and seminal plasma in the study population. Lipid peroxidation in seminal plasma, represented as MDA concentration, significantly increased by about 56% in the HE group and the percentage of motile sperm cells after 1 h decreased by about 34% in comparison to the control group. No statistically significant correlation between other parameters of sperm analysis and lead exposure parameters nor between lead, cadmium and zinc concentration in blood and seminal plasma were found. A positive association between lead intoxication parameters (PbB, ZPP, lead seminal plasma) and MDA concentration in sperm plasma and inverse correlation with sperm cells motility (PbB, ZPP) was found. An increased concentration of MDA was accompanied by a drop in sperm cells motility. In conclusion, we report that high exposure to lead causes a decrease of sperm motility in men most likely as a result of increased lipid peroxidation, especially if the level in the blood surpasses the concentration of 40 μg/dl

  5. Increased lipid peroxidation in pregnant women after iron and vitamin C supplementation.

    Science.gov (United States)

    Lachili, B; Hininger, I; Faure, H; Arnaud, J; Richard, M J; Favier, A; Roussel, A M

    2001-11-01

    Iron overload could promote the generation of free radicals and result in deleterious cellular damages. A physiological increase of oxidative stress has been observed in pregnancy. A routine iron supplement, especially a combined iron and vitamin C supplementation, without biological justifications (low hemoglobin [Hb] and iron stores) could therefore aggravate this oxidative risk. We investigated the effect of a daily combined iron supplementation (100 mg/d as fumarate) and vitamin C (500 mg/d as ascorbate) for the third trimester of pregnancy on lipid peroxidation (plasma TBARS), antioxidant micronutriments (Zn, Se, retinol, vitamin E, (beta-carotene) and antioxidant metalloenzymes (RBC Cu-Zn SOD and Se-GPX). The iron-supplemented group (n = 27) was compared to a control group (n = 27), age and number of pregnancies matched. At delivery, all the women exhibited normal Hb and ferritin values. In the supplemented group, plasma iron level was higher than in the control group (26.90 +/- 5.52 mmol/L) and TBARs plasma levels were significantly enhanced (p cell antioxidant metalloenzymes. Furthermore, the alpha-tocopherol plasma level was lowered in the iron-supplemented groups, suggesting an increased utilization of vitamin E. These data show that pharmalogical doses of iron, associated with high vitamin C intakes, can result in uncontrolled lipid peroxidation. This is predictive of adverse effects for the mother and the fetus. This study illustrates the potential harmful effects of iron supplementation when prescribed only on the assumption of anemia and not on the bases of biological criteria.

  6. Daconate Herbicide Toxicity on Lipid Peroxidation And Antioxidant Enzymes in Blood of Rats

    International Nuclear Information System (INIS)

    Tawfik, S.M.F.

    2005-01-01

    The effect of daconate herbicide on lipid peroxidation and antioxidant enzyme systems was investigated in rats after one and two weeks post-treatment. Animals were treated daily with an oral dose of 18 mg/kg body weight or 90 mg/kg body weight daconate for one and two consecutive weeks. Lipid peroxide content, as thiobarbituric acid reactive substances (TBARS), was determined in blood of rats as indication for cytotoxicity. Blood glutathion (GSH), gamma glutamyl transpeptidase (γ GT) and superoxide dismutase (SOD) were estimated as indication of antioxidant status. Also, daconate effect on peroxidase action of catalase in rats was studied using 14 C -formate. The results revealed significant elevation in TBARS level and γ GT activity accompanied by reduced level of GSH content and SOD activity after treatment of rats with a daily oral dose of 90 mg/kg for one and two weeks and also in rats treated with 18 mg/kg daconate for two weeks. Rats treated with daconate at the dose level of 18 mg/kg for one week revealed non-appreciable changes in the tested parameters of blood as compared to the control ones. Radioactivities eliminated in both the expired air and in urine were reduced at the dose level of 90 mg/kg after one and two weeks, while it were reduced only after two weeks at the dose level of 18 mg/kg daconate. The data revealed that daconate had a marked effect on the activities of catalase enzyme in blood and liver of treated rats

  7. Supplementation of xanthophylls increased antioxidant capacity and decreased lipid peroxidation in hens and chicks.

    Science.gov (United States)

    Gao, Yu-Yun; Xie, Qing-Mei; Ma, Jing-Yun; Zhang, Xiang-Bin; Zhu, Ji-Mei; Shu, Ding-Ming; Sun, Bao-Li; Jin, Ling; Bi, Ying-Zuo

    2013-03-28

    The present study investigated the effects of xanthophyll supplementation on production performance, antioxidant capacity (measured by glutathione peroxidase, superoxide dismutase (SOD), catalase, total antioxidant capacity (T-AOC), and reduced glutathione:oxidised glutathione ratio (GSH:GSSG)) and lipid peroxidation (measured by malondialdehyde (MDA)) in breeding hens and chicks. In Expt 1, 432 hens were fed diets supplemented with 0 (control group), 20 or 40 mg xanthophyll/kg diet. Blood samples were taken at 7, 14, 21, 28 and 35 d of the trial. Liver and jejunal mucosa were sampled at 35 d. Both xanthophyll groups improved serum SOD at 21 and 28 d, serum T-AOC at 21 d and liver T-AOC, and serum GSH:GSSG at 21, 28 and 35 d and liver GSH:GSSG. Xanthophylls also decreased serum MDA at 21 d in hens. Expt 2 was a 2 × 2 factorial design. Male chicks hatched from 0 or 40 mg in ovo xanthophyll/kg diet of hens were fed a diet containing either 0 or 40 mg xanthophyll/kg diet. Liver samples were collected at 0, 7, 14 and 21 d after hatching. Blood samples were also collected at 21 d. In ovo-deposited xanthophylls increased antioxidant capacity and decreased MDA in the liver mainly within 1 week after hatching. Maternal effects gradually vanished during 1-2 weeks after hatching. Dietary xanthophylls increased antioxidant capacity and decreased MDA in the liver and serum mainly from 2 weeks onwards. Data suggested that xanthophyll supplementation enhanced antioxidant capacity and reduced lipid peroxidation in different tissues of hens and chicks.

  8. DMSO does not protect against hydroxyl radical induced peroxidation in model membranes

    Energy Technology Data Exchange (ETDEWEB)

    Raleigh, J A; Kremers, W [Atomic Energy of Canada Ltd., Pinawa, Manitoba. Whiteshell Nuclear Research Establishment

    1981-04-01

    Dimethylsulphoxide (DMSO) promoted peroxidation in both linolenate and linoleate micelles. The promotional effect was most evident at concentrations of DMSO above 0.3 M with 0.012 M fatty acid. This was well above the DMSO concentration at which all the OH was scavenged by DMSO on the basis of the relative rate constants recorded. It was also found that DMSO did not decrease the yield of lipid hydroperoxide in a concentration range (0.01 to 0.1 M) where DMSO scavenges OH in competition with the unsaturated fatty acids. The sustaining mechanism could be accounted for in terms of CHsup(.)/sub 3/ and CH/sub 3/OOsup(.) being as effective as OH in initiating lipid peroxidation. A possible alternative explanation for the absence of protection by DMSO is that OH scavenging by DMSO is equivalent to lowering the dose-rate. The promotion of peroxidation at high DMSO concentration (> 1.0 M) was more difficult to account for, but may be analogous to the promotional effect of caesium and rubidium counterions.

  9. Coupling of lipid membrane elasticity and in-plane dynamics

    Science.gov (United States)

    Tsang, Kuan-Yu; Lai, Yei-Chen; Chiang, Yun-Wei; Chen, Yi-Fan

    2017-07-01

    Biomembranes exhibit liquid and solid features concomitantly with their in-plane fluidity and elasticity tightly regulated by cells. Here, we present experimental evidence supporting the existence of the dynamics-elasticity correlations for lipid membranes and propose a mechanism involving molecular packing densities to explain them. This paper thereby unifies, at the molecular level, the aspects of the continuum mechanics long used to model the two membrane features. This ultimately may elucidate the universal physical principles governing the cellular phenomena involving biomembranes.

  10. Stabilization of Lipid Membranes With Dendritic Polymers

    Science.gov (United States)

    2004-12-01

    Langmuir - Blodgett (Takamato, et al., 2001) and solution techniques (Johnson, et al., 2002). However, BLMs are too unstable to be used to make effective...J.A., Ivanova, A.T., Schwartz, D.K., Yang, T., and Cremer, P.S., 2001: Stable Ordering in Langmuir - Blodgett Films, Science, 293, 1292-1295. Tully...Various dendrimers and hyperbranched polymers were evaluated. In addition, lipids with different head groups were used to probe the underlying

  11. Mobility of drugs in lipid membranes by NMR

    International Nuclear Information System (INIS)

    Yoshii, Noriyuki; Okamura, Emiko

    2011-01-01

    Mobility of drugs and biomembrane constituents is a key to elucidate the membrane transport mechanism in the cell. Lipid bilayer membrane is a dynamic structure where molecules are always fluctuating under physiological conditions. The mechanism of drug transport is related to the molecular dynamics in such soft, fluid membrane interface. To gain insight into molecular movements in membranes, we develop a noninvasive method to monitor dynamics properties of drugs and lipid components in membranes by applying multinuclear high-resolution solution NMR in combination with the pulsed-field-gradient (PFG) technique. We have quantified the diffusivity, the kinetics of membrane binding, and the bound fraction of the drug in situ by using large unilamellar vesicles of egg phosphatidylcholine as model cell membranes. The combination of 1D and PFG NMR serves to quantify the kinetics of membrane binding where the bound and the free components are unable to distinguish because of the rapid exchange on the NMR timescale. A small-sized 5-fluorouracil and fluorinated bisphenol A are used as model drug. (author)

  12. Radioprotection by dipyridamole in the aging mouse. Effects on lipid peroxidation in mouse liver, spleen and brain after whole-body X-ray irradiation

    International Nuclear Information System (INIS)

    Seino, Noritaka

    1995-01-01

    To investigate the radioprotective effect of dipyridamole in the aging mouse, the lipid peroxide content in aging mouse liver, spleen and brain irradiated by X-ray were measured both before and after injection of dipyridamole. The lipid peroxide content increased with aging from 2 months old to 16 months old in the mouse liver, spleen and brain. The content of lipid peroxide in the liver and spleen of the aging mouse was significantly increased in 7 days after whole-body irradiation with 8 Gy, but was unchanged in the brain. Dipyridamole, given before irradiation, significantly inhibited the increase of lipid peroxide after irradiation. These results suggest that dipyridamole may have radioprotective effects on aging mouse liver and spleen as well as on young mouse, and that inhibition of lipid peroxidation is a possible factor in the radioprotective effect of dipyridamole. (author)

  13. Ageing mechanisms in chickpea seeds: Relationship of sugar hydrolysis and lipid peroxidation with Amadori and Millard reactions

    Directory of Open Access Journals (Sweden)

    mahdi shaaban

    2017-05-01

    Full Text Available This experiment was performed in order to study on ageing mechanisms of chickpea seeds (Cicer arietinum L. in natural storage and accelerated ageing conditions in seed laboratory of Gorgan Agricultural Science and Natural Resources, Gorgan, Iran at 2015. Experiment was in completely randomized design arrangement with four replications. Treatments were 2 and 4 years natural storage and 1-5 days of accelerated ageing with control treatment. The results showed that with increasing of natural storage and accelerated ageing duration, germination percentage was decreased. Increasing of ageing duration decreased soluble sugars, non-reducing sugars and soluble proteins but lipid peroxidation, reducing sugars, protein carbonylation and Amadori and Millard reaction were increased. In natural storage condition lipid peroxidation was more than sugar hydrolysis but in accelerated ageing condition sugar hydrolysis was more than lipid peroxidation. These results show that the main reason of Amadori and Millard reaction in chickpea seeds in natural storage condition is lipid peroxidation and in accelerated ageing condition is sugar hydrolysis. Also, the results showed that Amadori reaction in natural storage condition was more than Amadori reaction and in accelerated ageing condition Millard reaction was more than Amadori reaction. The results of the present study showed that sever Millard reaction after Amadori reaction induced higher damage on seed and results to more decrease of seed viability and reduce of seed germination percentage in accelerated ageing than natural storage.

  14. Effect of pomegranate supplementation and aerobic training on total antioxidant capacity and lipid peroxidation in overweight men

    Directory of Open Access Journals (Sweden)

    Soheila Rahimifardin

    2014-11-01

    Results: It was found that MDA index decreased in the pomegranate supplementation group compared to placebo group (P=0.016. But, total antioxidant capacity (TAC index in neither of the groups was significant (P=0.72. Conclusion: Results of the study indicate that pomegranate supplementation can reduce MDA derived from lipid peroxidation after 8 week running training in the obese. .

  15. Free radicals and lipid peroxidation mediated injury in burn trauma: the role of antioxidant therapy

    International Nuclear Information System (INIS)

    Horton, Jureta W.

    2003-01-01

    Burn trauma produces significant fluid shifts that, in turn, reduce cardiac output and tissue perfusion. Treatment approaches to major burn injury include administration of crystalloid solutions to correct hypovolemia and to restore peripheral perfusion. While this aggressive postburn volume replacement increases oxygen delivery to previously ischemic tissue, this restoration of oxygen delivery is thought to initiate a series of deleterious events that exacerbate ischemia-related tissue injury. While persistent hypoperfusion after burn trauma would produce cell death, volume resuscitation may exacerbate the tissue injury that occurred during low flow state. It is clear that after burn trauma, tissue adenosine triphosphate (ATP) levels gradually fall, and increased adenosine monophosphate (AMP) is converted to hypoxanthine, providing substrate for xanthine oxidase. These complicated reactions produce hydrogen peroxide and superoxide, clearly recognized deleterious free radicals. In addition to xanthine oxidase related free radical generation in burn trauma, adherent-activated neutrophils produce additional free radicals. Enhanced free radical production is paralleled by impaired antioxidant mechanisms; as indicated by burn-related decreases in superoxide dismutase, catalase, glutathione, alpha tocopherol, and ascorbic acid levels. Burn related upregulation of inducible nitric oxide synthase (iNOS) may produce peripheral vasodilatation, upregulate the transcription factor nuclear factor kappa B (NF-κB), and promote transcription and translation of numerous inflammatory cytokines. NO may also interact with the superoxide radical to yield peroxynitrite, a highly reactive mediator of tissue injury. Free radical mediated cell injury has been supported by postburn increases in systemic and tissue levels of lipid peroxidation products such as conjugated dienes, thiobarbituric acid reaction products, or malondialdehyde (MDA) levels. Antioxidant therapy in burn therapy

  16. [Methodological aspects of evaluation of potential lipid capacity for peroxidation from the serum levels of TBA-active products during iron ion stimulation].

    Science.gov (United States)

    Kulikova, A I; Tugusheva, F A; Zubina, I M; Shepilova, I N

    2008-05-01

    The authors propose a simple and reproducible procedure for using iron ions to stimulate serum lipid peroxidation, with TBA-active products being further determined. The procedure determines the reserve of lipids that can be oxidized during oxidative stress. A combination of direct studies and correlation analysis suggests that low-density lipoproteins and very low-density lipoproteins are the major substrates for lipid peroxidation while high-density lipoproteins show a high resistance to this process. The presented procedure may be used to monitor lipid peroxidation in various conditions and upon various exposures in common laboratory practice.

  17. Secondary radicals derived from chloramines of apolipoprotein B-100 contribute to HOCl-induced lipid peroxidation of low-density lipoproteins

    DEFF Research Database (Denmark)

    Hazell, L J; Davies, Michael Jonathan; Stocker, R

    1999-01-01

    component to be the major site of attack, whereas others describe extensive lipid peroxidation. The present study addresses this controversy. The results obtained are consistent with the hypothesis that radical-induced oxidation of LDL's lipids by HOCl is a secondary reaction, with most HOCl consumed via...... by an extended period of lipid peroxidation during which further protein oxidation does not occur. The secondary lipid peroxidation process involves EPR-detectable radicals, is attenuated by a radical trap or treatment of HOCl-oxidized LDL with methionine, and occurs less rapidly when the lipoprotein...

  18. Vesicle fusion with bilayer lipid membrane controlled by electrostatic interaction

    Directory of Open Access Journals (Sweden)

    Azusa Oshima

    2017-09-01

    Full Text Available The fusion of proteoliposomes is a promising approach for incorporating membrane proteins in artificial lipid membranes. In this study, we employed an electrostatic interaction between vesicles and supported bilayer lipid membranes (s-BLMs to control the fusion process. We combined large unilamellar vesicles (LUVs containing anionic lipids, which we used instead of proteoliposomes, and s-BLMs containing cationic lipids to control electrostatic interaction. Anionic LUVs were never adsorbed or ruptured on the SiO2 substrate with a slight negative charge, and selectively fused with cationic s-BLMs. The LUVs can be fused effectively to the target position. Furthermore, as the vesicle fusion proceeds and some of the positive charges are neutralized, the attractive interaction weakens and finally the vesicle fusion saturates. In other words, we can control the number of LUVs fused with s-BLMs by controlling the concentration of the cationic lipids in the s-BLMs. The fluidity of the s-BLMs after vesicle fusion was confirmed to be sufficiently high. This indicates that the LUVs attached to the s-BLMs were almost completely fused, and there were few intermediate state vesicles in the fusion process. We could control the position and amount of vesicle fusion with the s-BLMs by employing an electrostatic interaction.

  19. Simulation of Water Transport through a Lipid Membrane

    NARCIS (Netherlands)

    Marrink, Siewert-Jan; Berendsen, Herman J.C.

    1994-01-01

    To obtain insight in the process of water permeation through a lipid membrane, we performed molecular dynamics simulations on a phospholipid (DPPC)/water system with atomic detail. Since the actual process of permeation is too slow to be studied directly, we deduced the permeation rate indirectly

  20. Interaction of Dendritic Polymers with Synthetic Lipid and Cell Membranes

    Science.gov (United States)

    Mecke, Almut; Hong, Seungpyo; Bielinska, Anna U.; Banaszak Holl, Mark M.; Orr, Bradford G.; Baker, James R., Jr.

    2004-03-01

    Polyamidoamine (PAMAM) dendrimers are promising candidates for the development of nanoscale therapeutic transport agents. Here we present studies on dendrimer-membrane interactions leading to a better understanding of possible uptake mechanisms into cells. Using synthetic lipid and natural cell membranes as model systems it is shown that the effect of PAMAM dendrimers on a membrane strongly depends on the dendrimer generation, architecture and chemical properties of the branch end groups. Atomic force microscopy data indicates that generation 7 dendrimers have the ability to form small ( 10-100 nm) holes in a lipid bilayer. When dendrimers with otherwise identical chemical properties are arranged in a covalently linked cluster, no hole formation occurs. Dendrimer-lipid micelle formation is proposed and investigated as a possible mechanism for this behavior. Smaller dendrimers (generation 5) have a greatly reduced ability to remove lipid molecules from a bilayer. In addition to the size of the dendrimer, the charge of the branch end groups plays a significant role for dendrimer-membrane interactions. These results agree well with biological studies using cultured cells and point to a new mechanism of specific targeting and uptake into cells.

  1. Semiconductor particle mediated photoelectron transfers in bilayer lipid membranes

    International Nuclear Information System (INIS)

    Fendler, J.H.; Baral, S.

    1989-01-01

    This paper discusses semiconductor particles in situ generated on the cis surface of glyceryl monooleate (GMO) bilayer lipid membranes (BLMs), that have been used to mediate photoelectric effects. The presence of semiconductors on the BLM surface is addressed. The observed photoelectric effects are rationalized and presented

  2. Lipid-protein interactions in plasma membranes of fiber cells isolated from the human eye lens.

    Science.gov (United States)

    Raguz, Marija; Mainali, Laxman; O'Brien, William J; Subczynski, Witold K

    2014-03-01

    The protein content in human lens membranes is extremely high, increases with age, and is higher in the nucleus as compared with the cortex, which should strongly affect the organization and properties of the lipid bilayer portion of intact membranes. To assess these effects, the intact cortical and nuclear fiber cell plasma membranes isolated from human lenses from 41- to 60-year-old donors were studied using electron paramagnetic resonance spin-labeling methods. Results were compared with those obtained for lens lipid membranes prepared from total lipid extracts from human eyes of the same age group [Mainali, L., Raguz, M., O'Brien, W. J., and Subczynski, W. K. (2013) Biochim. Biophys. Acta]. Differences were considered to be mainly due to the effect of membrane proteins. The lipid-bilayer portions of intact membranes were significantly less fluid than lipid bilayers of lens lipid membranes, prepared without proteins. The intact membranes were found to contain three distinct lipid environments termed the bulk lipid domain, boundary lipid domain, and trapped lipid domain. However, the cholesterol bilayer domain, which was detected in cortical and nuclear lens lipid membranes, was not detected in intact membranes. The relative amounts of bulk and trapped lipids were evaluated. The amount of lipids in domains uniquely formed due to the presence of membrane proteins was greater in nuclear membranes than in cortical membranes. Thus, it is evident that the rigidity of nuclear membranes is greater than that of cortical membranes. Also the permeability coefficients for oxygen measured in domains of nuclear membranes were significantly lower than appropriate coefficients measured in cortical membranes. Relationships between the organization of lipids into lipid domains in fiber cells plasma membranes and the organization of membrane proteins are discussed. Copyright © 2014 Elsevier Ltd. All rights reserved.

  3. Effects of extremely low frequency electromagnetic fields on paraoxonase serum activity and lipid peroxidation metabolites in rat.

    Science.gov (United States)

    Seifirad, Soroush; Farzampour, Shahrokh; Nourbakhsh, Mitra; Amoli, Mahsa Mohammad; Razzaghy-Azar, Maryam; Larijani, Bagher

    2014-01-01

    Atherogenic effects of ELF-MF exposure have not been studied well so far. Therefore we have hypothesized that ELF-MF exposure might have atherogenic effect by impairing antioxidant function and increasing lipid peroxidation. This study was therefore undertaken to examine the effects of ELF-MF on paraoxonase (PON) activity, antioxidant capacity and lipid peroxidation metabolites. Effects of time on remodeling of antioxidant system were also investigated in this study. Seventy five Wistar rats were randomly allocated into five groups as follows: 1) Sham exposure, 2) Single exposure to 60 Hz, sacrificed immediately after exposure, 3) Single exposure to 60 Hz, sacrificed 72 hours after exposure, 4) Fourteen days of exposure to 60 Hz, sacrificed immediately after exposure, and 5) Fourteen days of exposure to 60 Hz, sacrificed 72 hours after exposure. Blood samples were collected and analyzed. The results were compared using ANOVA and post hoc Tukey HSD for multiple caparisons. Single ELF-MF exposure significantly increased lipid peroxidation (CD and MDA) and increased antioxidant serum activity (HDL, paraoxonase activity, and serum total antioxidant capacity). Chronic ELF-MF exposure increased lipid peroxidation and affected antioxidant system. Free fatty acids levels were significantly increased after both single and two weeks exposure. Chronic exposure led to irreversible changes while acute exposure tended to reversible alterations on above mentioned parameters. According to the results of this study, ELF-MF exposure could impair oxidant-antioxidant function and might increase oxidative stress and lipid peroxidation. Antioxidant capability was dependent on the duration and continuity of ELF-MF exposure.

  4. Investigations of antioxidant-mediated protection and mitigation of radiation-induced DNA damage and lipid peroxidation in murine skin.

    Science.gov (United States)

    Jelveh, Salomeh; Kaspler, Pavel; Bhogal, Nirmal; Mahmood, Javed; Lindsay, Patricia E; Okunieff, Paul; Doctrow, Susan R; Bristow, Robert G; Hill, Richard P

    2013-08-01

    Radioprotection and mitigation effects of the antioxidants, Eukarion (EUK)-207, curcumin, and the curcumin analogs D12 and D68, on radiation-induced DNA damage or lipid peroxidation in murine skin were investigated. These antioxidants were studied because they have been previously reported to protect or mitigate against radiation-induced skin reactions. DNA damage was assessed using two different assays. A cytokinesis-blocked micronucleus (MN) assay was performed on primary skin fibroblasts harvested from the skin of C3H/HeJ male mice 1 day, 1 week and 4 weeks after 5 Gy or 10 Gy irradiation. Local skin or whole body irradiation (100 kVp X-rays or caesium (Cs)-137 γ-rays respectively) was performed. DNA damage was further quantified in keratinocytes by immunofluorescence staining of γ-histone 2AX (γ-H2AX) foci in formalin-fixed skin harvested 1 hour or 1 day post-whole body irradiation. Radiation-induced lipid peroxidation in the skin was investigated at the same time points as the MN assay by measuring malondialdehyde (MDA) with a Thiobarbituric acid reactive substances (TBARS) assay. None of the studied antioxidants showed significant mitigation of skin DNA damage induced by local irradiation. However, when EUK-207 or curcumin were delivered before irradiation they provided some protection against DNA damage. In contrast, all the studied antioxidants demonstrated significant mitigating and protecting effects on radiation-induced lipid peroxidation at one or more of the three time points after local skin irradiation. Our results show no evidence for mitigation of DNA damage by the antioxidants studied in contrast to mitigation of lipid peroxidation. Since these agents have been reported to mitigate skin reactions following irradiation, the data suggest that changes in lipid peroxidation levels in skin may reflect developing skin reactions better than residual post-irradiation DNA damage in skin cells. Further direct comparison studies are required to confirm

  5. An ER Protein Functionally Couples Neutral Lipid Metabolism on Lipid Droplets to Membrane Lipid Synthesis in the ER

    DEFF Research Database (Denmark)

    Markgraf, Daniel F; Klemm, Robin W; Junker, Mirco

    2014-01-01

    Eukaryotic cells store neutral lipids such as triacylglycerol (TAG) in lipid droplets (LDs). Here, we have addressed how LDs are functionally linked to the endoplasmic reticulum (ER). We show that, in S. cerevisiae, LD growth is sustained by LD-localized enzymes. When LDs grow in early stationary...... phase, the diacylglycerol acyl-transferase Dga1p moves from the ER to LDs and is responsible for all TAG synthesis from diacylglycerol (DAG). During LD breakdown in early exponential phase, an ER membrane protein (Ice2p) facilitates TAG utilization for membrane-lipid synthesis. Ice2p has a cytosolic...... and explain how cells switch neutral lipid metabolism from storage to consumption....

  6. Thermal conductivity and rectification in asymmetric archaeal lipid membranes

    Science.gov (United States)

    Youssefian, Sina; Rahbar, Nima; Van Dessel, Steven

    2018-05-01

    Nature employs lipids to construct nanostructured membranes that self-assemble in an aqueous environment to separate the cell interior from the exterior environment. Membrane composition changes among species and according to environmental conditions, which allows organisms to occupy a wide variety of different habitats. Lipid bilayers are phase-change materials that exhibit strong thermotropic and lyotropic phase behavior in an aqueous environment, which may also cause thermal rectification. Among different types of lipids, archaeal lipids are of great interest due to their ability to withstand extreme conditions. In this paper, nonequilibrium molecular dynamics simulations were employed to study the nanostructures and thermal properties of different archaeols and to investigate thermal rectification effects in asymmetric archaeal membranes. In particular, we are interested in understanding the role of bridged phytanyl chains and cyclopentane groups in controlling the phase transition temperature and heat flow across the membrane. Our results indicate that the bridged phytanyl chains decrease the molecular packing of lipids, whereas the existence of cyclopentane rings on the tail groups increases the molecular packing by enhancing the interactions between isoprenoid chains. We found that macrocyclic archaeols have the highest thermal conductivity, whereas macrocyclic archaeols with two cyclopentane rings have the lowest. The effect of the temperature on the variation of thermal conductivity was found to be progressive. Our results further indicate that small thermal rectification effects occur in asymmetric archaeol bilayer membranes at around 25 K temperature gradient. The calculated thermal rectification factor was around 0.09 which is in the range of rectification factor obtained experimentally for nanostructures such as carbon nanotubes (0.07). Such phenomena may be of biological significance and could also be optimized for use in various engineering

  7. Quantitative studies of antimicrobial peptide-lipid membrane interactions

    DEFF Research Database (Denmark)

    Kristensen, Kasper

    antimicrobial peptides interact with phospholipid membranes. Motivated by that fact, the scope of this thesis is to study these antimicrobial peptide-lipid membrane interactions. In particular, we attempt to study these interactions with a quantitative approach. For that purpose, we consider the three...... a significant problem for quantitative studies of antimicrobial peptide-lipid membrane interactions; namely that antimicrobial peptides adsorb to surfaces of glass and plastic. Specifically, we demonstrate that under standard experimental conditions, this effect is significant for mastoparan X, melittin...... lead to inaccurate conclusions, or even completely wrong conclusions, when interpreting the FCS data. We show that, if all of the pitfalls are avoided, then FCS is a technique with a large potential for quantitative studies of antimicrobial peptide-induced leakage of fluorescent markers from large...

  8. Lipid engineering reveals regulatory roles for membrane fluidity in yeast flocculation and oxygen-limited growth

    DEFF Research Database (Denmark)

    Degreif, Daniel; de Rond, Tristan; Bertl, Adam

    2017-01-01

    Cells modulate lipid metabolism in order to maintain membrane homeostasis. Here we use a metabolic engineering approach to manipulate the stoichiometry of fatty acid unsaturation, a regulator of cell membrane fluidity, in Saccharomyces cerevisiae. Unexpectedly, reduced lipid unsaturation triggere...

  9. Role of charged lipids in membrane structures — Insight given by simulations

    DEFF Research Database (Denmark)

    Pöyry, Sanja; Vattulainen, Ilpo

    2016-01-01

    Lipids and proteins are the main components of cell membranes. It is becoming increasingly clear that lipids, in addition to providing an environment for proteins to work in, are in many cases also able to modulate the structure and function of those proteins. Particularly charged lipids...... to fruitful directions. In this paper, we review studies that have utilized molecular dynamics simulations to unravel the roles of charged lipids in membrane structures. We focus on lipids as active constituents of the membranes, affecting both general membrane properties as well as non-lipid membrane...

  10. [The composition of lipids and lipid peroxidation in the pancreas of quails exposed to nitrates and correction by the amaranth's seeds].

    Science.gov (United States)

    Tsekhmistrenko, S I; Ponomarenko, N V

    2013-01-01

    Researches of features of lipid composition, functioning of the system of antioxidant defense, maintenance of lipid peroxidation products in the quail's pancreas on the early postnatal ontogenesis stages are conducted for actions of nitrates and feeding with amaranth's seeds in mixed fodder. The arrival of nitrates in the organism of quails results in the decline of general lipids maintenance and nonetherified fat acids in the pancreas. Using of amaranth's seeds in mixed fodder on the background of the nitrate loading results in the increase of activity of the enzimes system of antioxidant defence, the growth of general lipid level in the quail's pancreas. Thus in correlation with separate classes of lipid maintenance of cholesterol goes down for certain, whereas the maintenance of triacylglycerols and ethers of cholesterol rises. The results obtained in the researches show the ability of amaranth's seeds to avert oxidative stress in quail's pancreas under nitrates influence.

  11. Triglyceride Blisters in Lipid Bilayers: Implications for Lipid Droplet Biogenesis and the Mobile Lipid Signal in Cancer Cell Membranes

    DEFF Research Database (Denmark)

    Khandelia, Himanshu; Duelund, Lars; Pakkanen, Kirsi Inkeri

    2010-01-01

    triolein molecules to the bilayer center in the form of a disordered, isotropic, mobile neutral lipid aggregate, at least 17 nm in diameter, which forms spontaneously, and remains stable on at least the microsecond time scale. The results give credence to the hotly debated existence of mobile neutral lipid...... aggregates of unknown function present in malignant cells, and to the early biogenesis of lipid droplets accommodated between the two leaflets of the endoplasmic reticulum membrane. The TO aggregates give the bilayer a blister-like appearance, and will hinder the formation of multi-lamellar phases in model...

  12. On the interaction between fluoxetine and lipid membranes: Effect of the lipid composition

    Science.gov (United States)

    Pham, Vy T.; Nguyen, Trinh Q.; Dao, Uyen P. N.; Nguyen, Trang T.

    2018-02-01

    Molecular interaction between the antidepressant fluoxetine and lipid bilayers was investigated in order to provide insights into the drug's incorporation to lipid membranes. In particular, the effects of lipid's unsaturation degree and cholesterol content on the partitioning of fluoxetine into large unilamellar vesicles (LUVs) comprised of unsaturated 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) and saturated 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) were evaluated using second derivative spectrophotometry and Attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR). It was found that fluoxetine partitioned to a greater extent into the liquid-crystalline DOPC LUVs than into the solid-gel DPPC LUVs. The lipid physical state dependence of drug partitioning was verified by increasing the temperature in which the partition coefficient of fluoxetine significantly increased upon the change of the lipid phase from solid-gel to liquid-crystalline. The incorporation of 28 mol% cholesterol into the LUVs exerted a significant influence on the drug partitioning into both DOPC and DPPC LUVs. The ATR-FTIR study revealed that fluoxetine perturbed the conformation of DOPC more strongly than that of DPPC due to the cis-double bonds in the lipid acyl chains. Fluoxetine possibly bound to the carbonyl moiety of the lipids through the hydrogen bonding formation while displaced some water molecules surrounding the PO2- regions of the lipid head groups. Cholesterol, however, could lessen the interaction between fluoxetine and the carbonyl groups of both DOPC and DPPC LUVs. These findings provided a better understanding of the role of lipid structure and cholesterol on the interaction between fluoxetine and lipid membranes, shedding more light into the drug's therapeutic action.

  13. Single Molecule Kinetics of ENTH Binding to Lipid Membranes

    Energy Technology Data Exchange (ETDEWEB)

    Rozovsky, Sharon [Univ. of Delaware, Newark, DE (United States); Forstner, Martin B. [Syracuse Univ., NY (United States); Sondermann, Holger [Cornell Univ., Ithaca, NY (United States); Groves, Jay T. [Univ. of California, Berkeley, CA (United States); Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-04-03

    Transient recruitment of proteins to membranes is a fundamental mechanism by which the cell exerts spatial and temporal control over proteins’ localization and interactions. Thus, the specificity and the kinetics of peripheral proteins’ membrane residence are an attribute of their function. In this article, we describe the membrane interactions of the interfacial epsin N-terminal homology (ENTH) domain with its target lipid phosphatidylinositol (4,5)-bisphosphate (PtdIns(4,5)P2). The direct visualization and quantification of interactions of single ENTH molecules with supported lipid bilayers is achieved using total internal reflection fluorescence microscopy (TIRFM) with a time resolution of 13 ms. This enables the recording of the kinetic behavior of ENTH interacting with membranes with physiologically relevant concentrations of PtdIns(4,5)P2 despite the low effective binding affinity. Subsequent single fluorophore tracking permits us to build up distributions of residence times and to measure ENTH dissociation rates as a function of membrane composition. In addition, due to the high time resolution, we are able to resolve details of the motion of ENTH associated with a simple, homogeneous membrane. In this case ENTH’s diffusive transport appears to be the result of at least three different diffusion processes.

  14. Dynamical and structural properties of lipid membranes in relation to liposomal drug delivery systems

    DEFF Research Database (Denmark)

    Jørgensen, Kent; Høyrup, Lise Pernille Kristine; Pedersen, Tina B.

    2001-01-01

    The structural and dynamical properties of DPPC liposomes containing lipopolymers (PEG-lipids) and charged DPPS lipids have been,studied in relation to the lipid membrane interaction of enzymes and peptides. The results suggest that both the lipid membrane structure and dynamics and in particular...

  15. Repeated mild traumatic brain injury in female rats increases lipid peroxidation in neurons.

    Science.gov (United States)

    Yates, Nathanael J; Lydiard, Stephen; Fehily, Brooke; Weir, Gillian; Chin, Aaron; Bartlett, Carole A; Alderson, Jacqueline; Fitzgerald, Melinda

    2017-07-01

    Negative outcomes of mild traumatic brain injury (mTBI) can be exacerbated by repeated insult. Animal models of repeated closed-head mTBI provide the opportunity to define acute pathological mechanisms as the number of mTBI increases. Furthermore, little is known about the effects of mTBI impact site, and how this may affect brain function. We use a closed head, weight drop model of mTBI that allows head movement following impact, in adult female rats to determine the role of the number and location of mTBI on brain pathology and behaviour. Biomechanical assessment of two anatomically well-defined mTBI impact sites were used, anterior (bregma) and posterior (lambda). Location of the impact had no significant effect on impact forces (450 N), and the weight impact locations were on average 5.4 mm from the desired impact site. No between location vertical linear head kinematic differences were observed immediately following impact, however, in the 300 ms post-impact, significantly higher mean vertical head displacement and velocity were observed in the mTBI lambda trials. Breaches of the blood brain barrier were observed with three mTBI over bregma, associated with immunohistochemical indicators of damage. However, an increased incidence of hairline fractures of the skull and macroscopic haemorrhaging made bregma an unsuitable impact location to model repeated mTBI. Repeated mTBI over lambda did not cause skull fractures and were examined more comprehensively, with outcomes following one, two or three mTBI or sham, delivered at 1 day intervals, assessed on days 1-4. We observe a mild behavioural phenotype, with subtle deficits in cognitive function, associated with no identifiable neuroanatomical or inflammatory changes. However, an increase in lipid peroxidation in a subset of cortical neurons following two mTBI indicates increasing oxidative damage with repeated injury in female rats, supported by increased amyloid precursor protein immunoreactivity with three m

  16. Effects of cisplatin on lipid peroxidation and the glutathione redox status in the liver of male rats: The protective role of selenium

    Directory of Open Access Journals (Sweden)

    Trbojević Ivana S.

    2010-01-01

    Full Text Available The role of oxidative stress in cisplatin (CP toxicity and its prevention by pretreatment with selenium (Se was investigated. Male Wistar albino rats were injected with a single dose of cisplatin (7.5 mg CP/kg b.m., i.p. and selenium (6 mg Se/kg b.m, as Na2SeO3, i.p. alone or in combination. The results suggest that CP intoxication induces oxidative stress and alters the glutathione redox status: reduced glutathione (GSH, oxidized glutathione (GSSG and the GSH/GSSG ratio (GSH RI, resulting in increased lipid peroxidation (LPO in rat liver. The pretreatment with selenium prior to CP treatment showed a protective effect against the toxic influence of CP on peroxidation of the membrane lipids and an altering of the glutathione redox status in the liver of rats. From our results we conclude that selenium functions as a potent antioxidant and suggest that it can control CP-induced hepatotoxicity in rats.

  17. How membrane lipids control the 3D structure and function of receptors

    Directory of Open Access Journals (Sweden)

    Jacques Fantini

    2018-02-01

    Full Text Available The cohabitation of lipids and proteins in the plasma membrane of mammalian cells is controlled by specific biochemical and biophysical rules. Lipids may be either constitutively tightly bound to cell-surface receptors (non-annular lipids or less tightly attached to the external surface of the protein (annular lipids. The latter are exchangeable with surrounding bulk membrane lipids on a faster time scale than that of non-annular lipids. Not only do non-annular lipids bind to membrane proteins through stereoselective mechanisms, they can also help membrane receptors acquire (or maintain a functional 3D structure. Cholesterol is the prototype of membrane lipids that finely controls the 3D structure and function of receptors. However, several other lipids such as sphingolipids may also modulate the function of membrane proteins though conformational adjustments. All these concepts are discussed in this review in the light of representative examples taken from the literature.

  18. Lipid packing drives the segregation of transmembrane helices into disordered lipid domains in model membranes

    NARCIS (Netherlands)

    Schaefer, Lars V.; de Jong, Djurre H.; Holt, Andrea; Rzepiela, Andrzej J.; de Vries, Alex H.; Poolman, Bert; Killian, J. Antoinette; Marrink, Siewert J.

    2011-01-01

    Cell membranes are comprised of multicomponent lipid and protein mixtures that exhibit a complex partitioning behavior. Regions of structural and compositional heterogeneity play a major role in the sorting and self-assembly of proteins, and their clustering into higher-order oligomers. Here, we use

  19. Structure and dynamics of water and lipid molecules in charged anionic DMPG lipid bilayer membranes

    International Nuclear Information System (INIS)

    Rønnest, A. K.; Peters, G. H.; Hansen, F. Y.; Taub, H.; Miskowiec, A.

    2016-01-01

    Molecular dynamics simulations have been used to investigate the influence of the valency of counter-ions on the structure of freestanding bilayer membranes of the anionic 1,2-dimyristoyl-sn-glycero-3-phosphoglycerol (DMPG) lipid at 310 K and 1 atm. At this temperature, the membrane is in the fluid phase with a monovalent counter-ion and in the gel phase with a divalent counter-ion. The diffusion constant of water as a function of its depth in the membrane has been determined from mean-square-displacement calculations. Also, calculated incoherent quasielastic neutron scattering functions have been compared to experimental results and used to determine an average diffusion constant for all water molecules in the system. On extrapolating the diffusion constants inferred experimentally to a temperature of 310 K, reasonable agreement with the simulations is obtained. However, the experiments do not have the sensitivity to confirm the diffusion of a small component of water bound to the lipids as found in the simulations. In addition, the orientation of the dipole moment of the water molecules has been determined as a function of their depth in the membrane. Previous indirect estimates of the electrostatic potential within phospholipid membranes imply an enormous electric field of 10 8 –10 9 V m −1 , which is likely to have great significance in controlling the conformation of translocating membrane proteins and in the transfer of ions and molecules across the membrane. We have calculated the membrane potential for DMPG bilayers and found ∼1 V (∼2 ⋅ 10 8 V m −1 ) when in the fluid phase with a monovalent counter-ion and ∼1.4 V (∼2.8 ⋅ 10 8 V m −1 ) when in the gel phase with a divalent counter-ion. The number of water molecules for a fully hydrated DMPG membrane has been estimated to be 9.7 molecules per lipid in the gel phase and 17.5 molecules in the fluid phase, considerably smaller than inferred experimentally for 1,2-dimyristoyl-sn-glycero-3

  20. Structure and dynamics of water and lipid molecules in charged anionic DMPG lipid bilayer membranes

    Energy Technology Data Exchange (ETDEWEB)

    Rønnest, A. K.; Peters, G. H.; Hansen, F. Y., E-mail: flemming@kemi.dtu.dk [Department of Chemistry, Technical University of Denmark, IK 207 DTU, DK-2800 Lyngby (Denmark); Taub, H.; Miskowiec, A. [Department of Physics and Astronomy and the University of Missouri Research Reactor,University of Missouri, Columbia, Missouri 65211 (United States)

    2016-04-14

    Molecular dynamics simulations have been used to investigate the influence of the valency of counter-ions on the structure of freestanding bilayer membranes of the anionic 1,2-dimyristoyl-sn-glycero-3-phosphoglycerol (DMPG) lipid at 310 K and 1 atm. At this temperature, the membrane is in the fluid phase with a monovalent counter-ion and in the gel phase with a divalent counter-ion. The diffusion constant of water as a function of its depth in the membrane has been determined from mean-square-displacement calculations. Also, calculated incoherent quasielastic neutron scattering functions have been compared to experimental results and used to determine an average diffusion constant for all water molecules in the system. On extrapolating the diffusion constants inferred experimentally to a temperature of 310 K, reasonable agreement with the simulations is obtained. However, the experiments do not have the sensitivity to confirm the diffusion of a small component of water bound to the lipids as found in the simulations. In addition, the orientation of the dipole moment of the water molecules has been determined as a function of their depth in the membrane. Previous indirect estimates of the electrostatic potential within phospholipid membranes imply an enormous electric field of 10{sup 8}–10{sup 9} V m{sup −1}, which is likely to have great significance in controlling the conformation of translocating membrane proteins and in the transfer of ions and molecules across the membrane. We have calculated the membrane potential for DMPG bilayers and found ∼1 V (∼2 ⋅ 10{sup 8} V m{sup −1}) when in the fluid phase with a monovalent counter-ion and ∼1.4 V (∼2.8 ⋅ 10{sup 8} V m{sup −1}) when in the gel phase with a divalent counter-ion. The number of water molecules for a fully hydrated DMPG membrane has been estimated to be 9.7 molecules per lipid in the gel phase and 17.5 molecules in the fluid phase, considerably smaller than inferred experimentally for 1

  1. Triglyceride blisters in lipid bilayers: implications for lipid droplet biogenesis and the mobile lipid signal in cancer cell membranes.

    Directory of Open Access Journals (Sweden)

    Himanshu Khandelia

    Full Text Available Triglycerides have a limited solubility, around 3%, in phosphatidylcholine lipid bilayers. Using millisecond-scale course grained molecular dynamics simulations, we show that the model lipid bilayer can accommodate a higher concentration of triolein (TO than earlier anticipated, by sequestering triolein molecules to the bilayer center in the form of a disordered, isotropic, mobile neutral lipid aggregate, at least 17 nm in diameter, which forms spontaneously, and remains stable on at least the microsecond time scale. The results give credence to the hotly debated existence of mobile neutral lipid aggregates of unknown function present in malignant cells, and to the early biogenesis of lipid droplets accommodated between the two leaflets of the endoplasmic reticulum membrane. The TO aggregates give the bilayer a blister-like appearance, and will hinder the formation of multi-lamellar phases in model, and possibly living membranes. The blisters will result in anomalous membrane probe partitioning, which should be accounted for in the interpretation of probe-related measurements.

  2. Effects of Loud Noise on Oxidation and Lipid peroxidation Variations of Liver Tissue of Rabbit

    Directory of Open Access Journals (Sweden)

    Mirzaei Ramazan

    2009-06-01

    Full Text Available Background: In today's world, noise is one of the major physical pollutants. The exact mechanism leading to tissue damage in loud noise is not clear. There are increasing evidences that show damage to cochlear tissue by noise is linked to cell injury induced by free radical species. The aim of this study was to investigate the relationship between change in liver tissue glutathione (anti- oxidant and malondialdehyde (one metabolite of lipid oxidation levels that occur in rabbits which were exposed to continuous loud noise.Materials and Methods: This experimental study was performed on 12 white Newzeland male rabbits in Tarbiat Modarres University in 2004. The rabbits were assigned to the following two groups: control, and exposed to continuous loud noise for 96 hours (8 h/day for 12 days, SPL=110dBA and 250Hz to 20 KHz. The concentration of malondialdehyde (MDA and glutathione (GSH in liver tissue samples were measured in rabbits after exposure to noise. Thiobarbituric acid reacting substance, Ellman's reagent and spectrophotometry techniques were used for this measurement. The data were statically analyzed by SPSS software and 2 groups were compared by t-test. Differences at the level of P<0.05 were considered statistically significant.Results: Comparison of the biochemical parameters of GSH and MDA measured in treated group with control indicated that antioxidant and lipid peroxidants parameters were suppressed in treated group compared to control group (p<0.05.Conclusion: Possible similarities between rabbit and human biological system indicate the possible role of noise in causation of oxidative stress in context with liver tissue impairm

  3. Effect of Copper on Fatty-Acid Composition and Peroxidation of Lipids in the Roots of Copper Tolerant and Sensitive Silene-Cucubalus.

    NARCIS (Netherlands)

    De Vos, C.H.R.; TenBookum, W.M.; Vooijs, R.; Schat, H.; De Kok, L.J.

    1993-01-01

    The effect of high copper exposure in vivo on the lipid and fatty acid composition and lipid peroxidation was studied in the roots of plants from one copper sensitive and two copper tolerant genotypes of Silene cucubalus. At 0.5 muM Cu (control treatment) the compositions of lipids and fatty acids

  4. Evaluation of antioxidant activity of Ruta graveolens L. extract on inhibition of lipid peroxidation and DPPH radicals and the effects of some external factors on plant extract's potency.

    Directory of Open Access Journals (Sweden)

    S. Mohammadi- Motamed

    2014-01-01

    Full Text Available The antioxidant properties of Ruta graveolens L. were evaluated by two different methods; free radical scavenging using DPPH and inhibition of lipid peroxidation by the ferric thiocyanate method. The IC50 value of the methanol extract in DPPH inhibition was 200.5 μg/mL which was acceptable in comparison with BHT (41.8 μg/mL. In thiocyanate method, the plant extract demonstrated activity as much as BHT in prevention of lipid peroxidation. Increasing the temperature during extraction, significantly decreased the extract power in inhibition of DPPH radicals. The storage time and temperature had no effect on lipid peroxidation inhibition.

  5. Structure and dynamics of water and lipid molecules in charged anionic DMPG lipid bilayer membranes

    DEFF Research Database (Denmark)

    Rønnest, A. K.; Peters, Günther H.J.; Hansen, Flemming Yssing

    2016-01-01

    Molecular dynamics simulations have been used to investigate the influence of the valency of counter-ions on the structure of freestanding bilayer membranes of the anionic 1,2-dimyristoyl-sn-glycero-3-phosphoglycerol (DMPG) lipid at 310 K and 1 atm. At this temperature, the membrane is in the fluid...... compared to experimental results and used to determine an average diffusion constant for all water molecules in the system. On extrapolating the diffusion constants inferred experimentally to a temperature of 310 K, reasonable agreement with the simulations is obtained. However, the experiments do not have...... the sensitivity to confirm the diffusion of a small component of water bound to the lipids as found in the simulations. In addition, the orientation of the dipole moment of the water molecules has been determined as a function of their depth in the membrane. Previous indirect estimates of the electrostatic...

  6. Ambient particulate air pollution from vehicles promotes lipid peroxidation and inflammatory responses in rat lung.

    Science.gov (United States)

    Pereira, C E L; Heck, T G; Saldiva, P H N; Rhoden, C R

    2007-10-01

    Oxidative stress plays a major role in the pathogenesis of particle-dependent lung injury. Ambient particle levels from vehicles have not been previously shown to cause oxidative stress to the lungs. The present study was conducted to a) determine whether short-term exposure to ambient levels of particulate air pollution from vehicles elicits inflammatory responses and lipid peroxidation in rat lungs, and b) determine if intermittent short-term exposures (every 4 days) induce some degree of tolerance. Three-month-old male Wistar rats were exposed to ambient particulate matter (PM) from vehicles (N = 30) for 6 or 20 continuous hours, or for intermittent (5 h) periods during 20 h for 4 consecutive days or to filtered air (PM polluted air for 20 h (P-20) showed a significant increase in the total number of leukocytes in bronchoalveolar lavage compared to control (C-20: 2.61 x 105 +/- 0.51;P-20: 5.01 x 105 +/- 0.81; P air pollution did not cause a significant increase in lung water content. These data suggest oxidative stress as one of the mechanisms responsible for the acute adverse respiratory effects of particles, and suggest that short-term inhalation of ambient particulate air pollution from street with high automobile traffic represents a biological hazard.

  7. Experimental studies on anti-oxidants reducing lipid peroxidation of irradiated mice

    International Nuclear Information System (INIS)

    Du Zeji; Liu Keliang; Su Liaoyuan

    1993-08-01

    The free radical plays an important role in the irradiation damage. The irradiation damage would be reduced if anti-oxidants is used, because anti-oxidants can scavenge free radicals and suppress lipid peroxidation. In the study, a fluoro-spectrophotometer was used to determine the changes of MDA levels in mice tissues and serum after irradiation and the protective effect of anti-oxidants of Vit E and DMSO on damage caused by free radicals. The results are as follows: (1) The highest MDA level was at 12 to 24 hours after irradiation dose of 3.0 Gy. (2) The MDA level is increasing with the increasing of irradiation dose. It means the MDA level can indicate the extent of irradiation damage. (3) Both Vit E and DMSO had a powerful effect on reducing MDA level, but the effect of DMSO was stronger than Vit E. The optimum doses of them were 0.25 mg/g body weight and 10 mg/g body weight respectively. (4) The best effect obtained was to use Vit E and DMSO simultaneously

  8. Lipid peroxidation and Alzheimer’s disease: Key role of Amyloid-β

    Directory of Open Access Journals (Sweden)

    Kontush Anatol

    2006-01-01

    Full Text Available Increased lipid peroxidation and elevated oxidative stress represent well-established characteristics of Alzheimer’s disease (AD. Amyloid-β (Aβ peptide, a major component of amyloid plaques, can strongly influence oxidative processes. In aggregated form, Aβ has prooxidative properties, whereas in monomeric form it functions as an antioxidant. The antioxidative properties of monomeric Aβ are related to its ability to chelate transition metal ions, which are potent catalysts of oxidation. Aβ possesses an amphiphilic structure, associates with lipoproteins in vivo and may therefore function as a preventive antioxidant which protects lipoproteins from oxidation by transition metal ions. Increased production of Aβ in response to elevated oxidative stress has been documented in a number of in vitro studies, implying that production of monomeric Aβ as a lipoprotein antioxidant can be abnormally increased in response to elevated oxidative stress in aging. Subsequent accumulation of Aβ-metal aggregates, production of reactive oxygen species and toxic action to neuronal cells may represent a gain-of-function transformation and form temporal sequence of events in the development of AD.

  9. A high throughput biochemical fluorometric method for measuring lipid peroxidation in HDL.

    Directory of Open Access Journals (Sweden)

    Theodoros Kelesidis

    Full Text Available Current cell-based assays for determining the functional properties of high-density lipoproteins (HDL have limitations. We report here the development of a new, robust fluorometric cell-free biochemical assay that measures HDL lipid peroxidation (HDLox based on the oxidation of the fluorochrome Amplex Red. HDLox correlated with previously validated cell-based (r = 0.47, p<0.001 and cell-free assays (r = 0.46, p<0.001. HDLox distinguished dysfunctional HDL in established animal models of atherosclerosis and Human Immunodeficiency Virus (HIV patients. Using an immunoaffinity method for capturing HDL, we demonstrate the utility of this novel assay for measuring HDLox in a high throughput format. Furthermore, HDLox correlated significantly with measures of cardiovascular diseases including carotid intima media thickness (r = 0.35, p<0.01 and subendocardial viability ratio (r = -0.21, p = 0.05 and physiological parameters such as metabolic and anthropometric parameters (p<0.05. In conclusion, we report the development of a new fluorometric method that offers a reproducible and rapid means for determining HDL function/quality that is suitable for high throughput implementation.

  10. Recovery of motor deficit, cerebellar serotonin and lipid peroxidation levels in the cortex of injured rats.

    Science.gov (United States)

    Bueno-Nava, Antonio; Gonzalez-Pina, Rigoberto; Alfaro-Rodriguez, Alfonso; Nekrassov-Protasova, Vladimir; Durand-Rivera, Alfredo; Montes, Sergio; Ayala-Guerrero, Fructuoso

    2010-10-01

    The sensorimotor cortex and the cerebellum are interconnected by the corticopontocerebellar (CPC) pathway and by neuronal groups such as the serotonergic system. Our aims were to determine the levels of cerebellar serotonin (5-HT) and lipid peroxidation (LP) after cortical iron injection and to analyze the motor function produced by the injury. Rats were divided into the following three groups: control, injured and recovering. Motor function was evaluated using the beam-walking test as an assessment of overall locomotor function and the footprint test as an assessment of gait. We also determined the levels of 5-HT and LP two and twenty days post-lesion. We found an increase in cerebellar 5-HT and a concomitant increase in LP in the pons and cerebellum of injured rats, which correlated with their motor deficits. Recovering rats showed normal 5-HT and LP levels. The increase of 5-HT in injured rats could be a result of serotonergic axonal injury after cortical iron injection. The LP and motor deficits could be due to impairments in neuronal connectivity affecting the corticospinal and CPC tracts and dysmetric stride could be indicative of an ataxic gait that involves the cerebellum.

  11. Drinking carrot juice increases total antioxidant status and decreases lipid peroxidation in adults

    Directory of Open Access Journals (Sweden)

    Patil Bhimanagouda S

    2011-09-01

    Full Text Available Abstract Background High prevalence of obesity and cardiovascular disease is attributable to sedentary lifestyle and eating diets high in fat and refined carbohydrate while eating diets low in fruit and vegetables. Epidemiological studies have confirmed a strong association between eating diets rich in fruits and vegetables and cardiovascular health. The aim of this pilot study was to determine whether drinking fresh carrot juice influences antioxidant status and cardiovascular risk markers in subjects not modifying their eating habits. Methods An experiment was conducted to evaluate the effects of consuming 16 fl oz of daily freshly squeezed carrot juice for three months on cardiovascular risk markers, C-reactive protein, insulin, leptin, interleukin-1α, body fat percentage, body mass index (BMI, blood pressure, antioxidant status, and malondialdehyde production. Fasting blood samples were collected pre-test and 90 days afterward to conclude the study. Results Drinking carrot juice did not affect (P > 0.1 the plasma cholesterol, triglycerides, Apo A, Apo B, LDL, HDL, body fat percentage, insulin, leptin, interleukin-1α, or C-reactive protein. Drinking carrot juice decreased (P = 0.06 systolic pressure, but did not influence diastolic pressure. Drinking carrot juice significantly (P Conclusion Drinking carrot juice may protect the cardiovascular system by increasing total antioxidant status and by decreasing lipid peroxidation independent of any of the cardiovascular risk markers measured in the study.

  12. The metabolism of carbohydrates and lipid peroxidation in lead-exposed workers.

    Science.gov (United States)

    Kasperczyk, Aleksandra; Dobrakowski, Michal; Ostałowska, Alina; Zalejska-Fiolka, Jolanta; Birkner, Ewa

    2015-12-01

    The present study was undertaken to estimate the effect of occupational exposure to lead on the blood concentration of glucose and several enzymes involved in glycolysis, the citric acid cycle, and the pentose phosphate pathway. To estimate the degree of lipid peroxidation, the concentrations of conjugated dienes were determined. The examined group included 145 healthy male employees of lead-zinc works. Taking into account the mean blood lead levels, the examined group was divided into two subgroups. The control group was composed of 36 healthy male administrative workers. The markers of lead exposure were significantly elevated in both subgroups when compared with the controls. There were no significant changes in fasting glucose concentration and fructose-1,6-bisphosphate aldolase activity in the study population. The concentration of conjugated dienes was significantly higher in both subgroups, whereas the activity of malate dehydrogenase was significantly higher only in the group with higher exposure. The activities of lactate dehydrogenase and sorbitol dehydrogenase were significantly decreased in the examined subgroups. The activity of glucose-6-phosphate dehydrogenase decreased significantly in the group with higher exposure and could be the cause of the elevated concentrations of conjugated dienes. It is possible to conclude that lead interferes with carbohydrate metabolism, but compensatory mechanisms seem to be efficient, as glucose homeostasis in lead-exposed workers was not disturbed. © The Author(s) 2013.

  13. Protective effects of Sonchus asper against KBrO3 induced lipid peroxidation in rats.

    Science.gov (United States)

    Khan, Rahmat Ali; Khan, Muhammad Rashid; Sahreen, Sumaira

    2012-11-27

    Sonchus asper is traditionally used in Pakistan for the treatment of reproductive dysfunction and oxidative stress. The present investigation was aimed to evaluate chloroform extract of Sonchus asper (SACE) against potassium bromate-induced reproductive stress in male rats. 20 mg/kg body weight (b.w.) potassium bromate (KBrO3) was induced in 36 rats for four weeks and checked the protective efficacy of SACE at various hormonal imbalances, alteration of antioxidant enzymes, and DNA fragmentation levels. High performance chromatography (HPLC) was used for determination of bioactive constituents responsible. The level of hormonal secretion was significantly altered by potassium bromate. DNA fragmentation%, activity of antioxidant enzymes; catalase (CAT), peroxidase (POD), superoxide dismutase (SOD) and phase II metabolizing enzymes viz; glutathione reductase (GSR), glutathione peroxidase (GSHpx), glutathione-S-tansase (GST) and reduced glutathione (GSH) was decreased while hydrogen per oxide contents and thiobarbituric acid reactive substances (TBARS) were increased with KBrO3 treatment. Treatment with SACE effectively ameliorated the alterations in the biochemical markers; hormonal and molecular levels while HPLC characterization revealed the presence of catechin, kaempferol, rutin and quercetin. Protective effects of Sonchus asper vs. KBrO3 induced lipid peroxidation might be due to bioactive compound present in SACE.

  14. Protective effects of Sonchus asper against KBrO3 induced lipid peroxidation in rats

    Directory of Open Access Journals (Sweden)

    Khan Rahmat Ali

    2012-11-01

    Full Text Available Abstract Background Sonchus asper is traditionally used in Pakistan for the treatment of reproductive dysfunction and oxidative stress. The present investigation was aimed to evaluate chloroform extract of Sonchus asper (SACE against potassium bromate-induced reproductive stress in male rats. Methods 20 mg/kg body weight (b.w. potassium bromate (KBrO3 was induced in 36 rats for four weeks and checked the protective efficacy of SACE at various hormonal imbalances, alteration of antioxidant enzymes, and DNA fragmentation levels. High performance chromatography (HPLC was used for determination of bioactive constituents responsible. Results The level of hormonal secretion was significantly altered by potassium bromate. DNA fragmentation%, activity of antioxidant enzymes; catalase (CAT, peroxidase (POD, superoxide dismutase (SOD and phase II metabolizing enzymes viz; glutathione reductase (GSR, glutathione peroxidase (GSHpx, glutathione-S-tansase (GST and reduced glutathione (GSH was decreased while hydrogen per oxide contents and thiobarbituric acid reactive substances (TBARS were increased with KBrO3 treatment. Treatment with SACE effectively ameliorated the alterations in the biochemical markers; hormonal and molecular levels while HPLC characterization revealed the presence of catechin, kaempferol, rutin and quercetin. Conclusion Protective effects of Sonchus asper vs. KBrO3 induced lipid peroxidation might be due to bioactive compound present in SACE.

  15. Facile Fabrication of a Gold Nanocluster-Based Membrane for the Detection of Hydrogen Peroxide

    Directory of Open Access Journals (Sweden)

    Pu Zhang

    2016-07-01

    Full Text Available In this work, we present a simple and rapid method to synthesize red luminescent gold nanoclusters (AuNCs with high quantum yield (QY, ~16%, excellent photostability and biocompatibility. Next, we fabricated a solid membrane by loading the as-prepared AuNCs in an agar matrix. Different from nanomaterials dispersed in solution, the AuNCs-based solid membrane has distinct advantages including convenience of transportation, while still maintaining strong red luminescence, and relatively long duration storage without aggregation. Taking hydrogen peroxide (H2O2 as a typical example, we then employed the AuNCs as a luminescent probe and investigated their sensing performance, either in solution phase or on a solid substrate. The detection of H2O2 could be achieved in wide concentration ranges over 805 nM–1.61 mM and 161 μM–19.32 mM in solution and on a solid membrane, respectively, with limits of detection (LOD of 80 nM and 20 μM. Moreover, the AuNCs-based membrane could also be used for visual detection of H2O2 in the range of 0–3.22 mM. In view of the convenient synthesis route and attractive luminescent properties, the AuNCs-based membrane presented in this work is quite promising for applications such as optical sensing, fluorescent imaging, and photovoltaics.

  16. The Effects of Subacute Exposure of Peracetic Acid on Lipid Peroxidation and Hepatic Enzymes in Wistar Rats

    Science.gov (United States)

    Marjani, Abdoljalal; Golalipour, Mohammad J.; Gharravi, Anneh M.

    2010-01-01

    Objectives This study was undertaken to determine the effect of subacute exposure of peracetic acid on lipid peroxidation and hepatic enzymes in Wistar rats. Methods 48 male animals in Treatment Group I, II and III received 0.2%, 2% and 20% peracetic acid daily for 2 and 4 weeks. Results Serum malondialdehyde increased and Alanine Transaminase and Aspartate Transaminase decreased significantly in groups 2 and 3, compared to the control group. The malondialdehyde, Alanine Transaminase and Aspartate Transaminase with 0.2% and 2% doses of peracetic acid for 2 weeks do not lead to the alteration of malondialdehyde and enzyme activities. Conclusion This study demonstrated that the enhancement of malondialdehyde could provide an oxidative damage induced by disinfectant peroxidation at 20% and 2% doses at 2 and 4 weeks. The consumption of peroxidation with 20% for 2 weeks and 2% for 4 weeks can cause the increase of malondialdehyde and the decrease of enzyme activities, respectively. PMID:22043353

  17. Polymalic Acid Tritryptophan Copolymer Interacts with Lipid Membrane Resulting in Membrane Solubilization

    Directory of Open Access Journals (Sweden)

    Hui Ding

    2017-01-01

    Full Text Available Anionic polymers with membrane permeation functionalities are highly desirable for secure cytoplasmic drug delivery. We have developed tritryptophan containing copolymer (P/WWW of polymalic acid (PMLA that permeates membranes by a mechanism different from previously described PMLA copolymers of trileucine (P/LLL and leucine ethyl ester (P/LOEt that use the “barrel stave” and “carpet” mechanism, respectively. The novel mechanism leads to solubilization of membranes by forming copolymer “belts” around planar membrane “packages.” The formation of such packages is supported by results obtained from studies including size-exclusion chromatography, confocal microscopy, and fluorescence energy transfer. According to this “belt” mechanism, it is hypothesized that P/WWW first attaches to the membrane surface. Subsequently the hydrophobic tryptophan side chains translocate into the periphery and insert into the lipid bilayer thereby cutting the membrane into packages. The reaction is driven by the high affinity between the tryptophan residues and lipid side chains resulting in a stable configuration. The formation of the membrane packages requires physical agitation suggesting that the success of the translocation depends on the fluidity of the membrane. It is emphasized that the “belt” mechanism could specifically function in the recognition of abnormal cells with high membrane fluidity and in response to hyperthermia.

  18. Air pollutant sulfur dioxide-induced alterations on the levels of lipids, lipid peroxidation and lipase activity in various regions of the rat brain

    Energy Technology Data Exchange (ETDEWEB)

    Haider, S S; Hasan, M; Khan, N H

    1982-07-01

    The exposure of rats to SO/sub 2/ (10 p.p.m.) for one hour daily for 30 days caused depletion of total lipids in all brain areas. The contents of phospholipid were elevated in cerebellum and brain stem, but were depleted in cerebral hemisphere. Cholesterol levels showed an increase in various brain regions. On the other hand, gangliosides were increased in cerebellum and brain stem, but were decreased in cerebral hemisphere. Interestingly, cholesterol/phospholipid ratio was increased in different regions of the brain. Lipase activity was elevated in cerebral hemisphere. Lipid peroxidation showed marked increment in whole brain and in all the brain areas studied. The results suggest that SO/sub 2/-exposure induces degradation of lipids. Interestingly, the lipid contents are affected differentially in the various parts of the brain.

  19. Suppression by ellagic acid of 60Co-irradiation-induced lipid peroxidation in placenta and fetus of rats

    International Nuclear Information System (INIS)

    Oku, Hirotsugu

    1992-01-01

    The effect of ellagic acid, a component of Eucalyptus maculata, on lipid peroxidation was examined in placenta and fetus of pregnant rats irradiated with 60 Co. The increase in lipid peroxide levels by the irradiation of the placenta and fetus brain as well as those of the serum and organs of mother was suppressed by treatment of the mother rats with ellagic acid. This suppressing effect found in placenta and fetus was significantly correlated with that found in mother rats. Moreover, ellagic acid suppressed the morphological changes such as degeneration in the endothelial cells of placenta and liver cells of fetus caused by the irradiation and improved the survival rate after the irradiation. These suppressing effects of ellagic acid were approximately the same as those of α-tocopherol. (author)

  20. Effect of dietary Astaxanthin sources supplementation on muscle pigmentation and lipid peroxidation in rainbow trout (Oncorhynchus mykiss

    Directory of Open Access Journals (Sweden)

    Marco Saroglia

    2010-01-01

    Full Text Available Astaxanthin is one of the major carotenoids in aquatic animals including salmonid fishes and is the preferred pigments added to salmon feed. It’s also a powerful antioxidant compared to other carotenoids and that may confer numerous health benefits. The aim of the present experi- ment was to investigate the effect of Astaxanthin deposition on the lipids peroxidation by studying the Malondialdeide (MDA level in muscle of rainbow trout (Oncorhynchus mykiss. The Astaxanthin concentrations in fish fed with a commercial sources as Lucantin®Pink (BASF Ludwigshafen, Ger- many reached values to 5.76±0.18x10-3 mg/g after 50 days feeding, while the MDA concentration de- creased from 1.56x103 to 0.45x103 ng/g. The correlation between MDA and Astaxanthin concentrations decreased linearly and confirmed the antioxidant properties of the pigment by reducing the lipids peroxidation.

  1. Protective effect of serotonin on phospholipids and lipid peroxides contents in brain and liver of gamma irradiated rats

    International Nuclear Information System (INIS)

    Mohamed, M.A.; Saada, H.A.

    1999-01-01

    Treatment of normal rats with serotonin (2 mg/100 g body weight) produced no significant change in levels of phospholipids and lipid peroxides of the cerebral hemispheres and liver 1,3 and days after treatment. The content of lipid peroxides was measured as malondialdehyde (MDA). Whole body gamma-irradiation of rats at 8 Gy resulted in significant decrease in the level of phospholipids and significant increase in MDA level in cerebral hemispheres and lever. Changes were more pronounced in liver. Treatment with serotonin, 15 minutes before irradiation, had a pronounced protective effect against the radiation induced changes in the levels of phospholipids and MDA only in the liver through all the experimental period

  2. Polymer-Induced Swelling of Solid-Supported Lipid Membranes

    Directory of Open Access Journals (Sweden)

    Martin Kreuzer

    2015-12-01

    Full Text Available In this paper, we study the interaction of charged polymers with solid-supported 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC membranes by in-situ neutron reflectivity. We observe an enormous swelling of the oligolamellar lipid bilayer stacks after incubation in solutions of poly(allylamine hydrochloride (PAH in D2O. The positively charged polyelectrolyte molecules interact with the lipid bilayers and induce a drastic increase in their d-spacing by a factor of ~4. Temperature, time, and pH influence the swollen interfacial lipid linings. From our study, we conclude that electrostatic interactions introduced by the adsorbed PAH are the main cause for the drastic swelling of the lipid coatings. The DMPC membrane stacks do not detach from their solid support at T > Tm. Steric interactions, also introduced by the PAH molecules, are held responsible for the stabilizing effect. We believe that this novel system offers great potential for fundamental studies of biomembrane properties, keeping the membrane’s natural fluidity and freedom, decoupled from a solid support at physiological conditions.

  3. Reorganization of plasma membrane lipid domains during conidial germination.

    Science.gov (United States)

    Santos, Filipa C; Fernandes, Andreia S; Antunes, Catarina A C; Moreira, Filipe P; Videira, Arnaldo; Marinho, H Susana; de Almeida, Rodrigo F M

    2017-02-01

    Neurospora crassa, a filamentous fungus, in the unicellular conidial stage has ideal features to study sphingolipid (SL)-enriched domains, which are implicated in fundamental cellular processes ranging from antifungal resistance to apoptosis. Several changes in lipid metabolism and in the membrane composition of N. crassa occur during spore germination. However, the biophysical impact of those changes is unknown. Thus, a biophysical study of N. crassa plasma membrane, particularly SL-enriched domains, and their dynamics along conidial germination is prompted. Two N. crassa strains, wild-type (WT) and slime, which is devoid of cell wall, were studied. Conidial growth of N. crassa WT from a dormancy state to an exponential phase was accompanied by membrane reorganization, namely an increase of membrane fluidity, occurring faster in a supplemented medium than in Vogel's minimal medium. Gel-like domains, likely enriched in SLs, were found in both N. crassa strains, but were particularly compact, rigid and abundant in the case of slime cells, even more than in budding yeast Saccharomyces cerevisiae. In N. crassa, our results suggest that the melting of SL-enriched domains occurs near growth temperature (30°C) for WT, but at higher temperatures for slime. Regarding biophysical properties strongly affected by ergosterol, the plasma membrane of slime conidia lays in between those of N. crassa WT and S. cerevisiae cells. The differences in biophysical properties found in this work, and the relationships established between membrane lipid composition and dynamics, give new insights about the plasma membrane organization and structure of N. crassa strains during conidial growth. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Protective Effect of Pulp Oil Extracted from Canarium odontophyllum Miq. Fruit on Blood Lipids, Lipid Peroxidation, and Antioxidant Status in Healthy Rabbits

    Directory of Open Access Journals (Sweden)

    Faridah Hanim Shakirin

    2012-01-01

    Full Text Available The aim of this paper was to compare the effects of pulp and kernel oils of Canarium odontophyllum Miq. (CO on lipid profile, lipid peroxidation, and oxidative stress of healthy rabbits. The oils are rich in SFAs and MUFAs (mainly palmitic and oleic acids. The pulp oil is rich in polyphenols. Male New Zealand white (NZW rabbits were fed for 4 weeks on a normal diet containing pulp (NP or kernel oil (NK of CO while corn oil was used as control (NC. Total cholesterol (TC, HDL-C, LDL-c and triglycerides (TG levels were measured in this paper. Antioxidant enzymes (superoxide dismutase and glutathione peroxidise, thiobarbiturate reactive substances (TBARSs, and plasma total antioxidant status (TAS were also evaluated. Supplementation of CO pulp oil resulted in favorable changes in blood lipid and lipid peroxidation (increased HDL-C, reduced LDL-C, TG, TBARS levels with enhancement of SOD, GPx, and plasma TAS levels. Meanwhile, supplementation of kernel oil caused lowering of plasma TC and LDL-C as well as enhancement of SOD and TAS levels. These changes showed that oils of CO could be beneficial in improving lipid profile and antioxidant status as when using part of normal diet. The oils can be used as alternative to present vegetable oil.

  5. The effect of EGb 761 on retinal lipid peroxidation and glutathione peroxidase level in experimental lens induced uveitis.

    Science.gov (United States)

    Bilgihan, A; Aricioğlu, A; Bilgihan, K; Onol, M; Hasanreisoğlu, B; Türközkan, N

    1994-01-01

    An acute lens-induced necrotizing intraocular inflammation was produced in pigmented guinea pigs. Treatment of these animals by 100 mg/kg/day EGb 761 a free oxygen radical scavenger for 10 days, reduced retinal lipid peroxidation (p > 0.05) and increased the retinal glutathione peroxidase level (p > 0.05). Although not significantly, these findings suggest that EGb 761 could be combined with other antiinflammatory drugs and may be beneficial in the treatment of uveitis.

  6. The influence of L-DOPA on the accumulation of lipid peroxidation products in some brain structures affected by radiation

    International Nuclear Information System (INIS)

    Babaev, R.A.; Kocharli, R.Kh.; Akhmedova, G.Sh.; Gasanova, A.A.; Babaev, Kh.F.

    1990-01-01

    A study was made of the effect of L-DOPA on the dynamics of changes in lipid peroxidation products (LPP) and the content of various types of SH-groups in certain brain structures (oblongata, cerebellum, visual and sensorimotor cortex) and their synaptosomal fractions upon irradiation. The preadministration of L-DOPA to irradiated rats inhibited LPP accumulation, prevented the decrease in the content of various types of thiols and thus exerted an antioxidant effect

  7. Medicinal Mushroom Cracked-Cap Polypore, Phellinus rimosus (Higher Basidiomycetes) Attenuates Acute Ethanol-Induced Lipid Peroxidation in Mice.

    Science.gov (United States)

    Ajith, Thekkuttuparambil A; Janardhanan, Kainoor K

    2015-01-01

    Alcohol abuse and alcoholism remain one of the major health issues worldwide, especially in developing countries. The protective effect of Phellinus rimosus against acute alcohol-induced lipid peroxidation in the liver, kidney, and brain as well as its effect against antioxidant enzyme activity such as superoxide (SOD) and catalase (CAT) in the liver was evaluated in mice. Ethyl acetate extract of Ph. Rimosus (50 mg/kg body wt, p.o.) 1 h before each administration of alcohol (3 mL/kg, p.o.; total 2 doses at 24-h intervals) protected against lipid peroxidation in all organs and attenuated the decline of SOD and CAT activity in the liver. The fold increase in lipid peroxidation, including conjugated diene and thiobarbituric acid reactive substance (TBARS) levels, was highest in the liver. There were 2.6- and 1.5- fold increases in TBARS levels in the liver of the alcohol alone- and alcohol+Ph. Rimosus-treated groups, compared with that of the normal group. Activity of SOD and CAT in the liver of alcohol- and alcohol+Ph. Rimosus- treated animals was 9.05±1.38, 18.76±1.71, and 11.26±1.02, 31.58±3.35 IU/mg protein, respectively. Extract at 1 mg/mL inhibited 50.6% activity of aniline hydroxylase (CYP2E1) in liver homogenate. From these results, we concluded that the extract significantly protected against the lipid peroxidation. Protection in the liver may be due to the inhibitory effect on CYP2E1 as well as the direct radical scavenging effect of Ph. Rimosus, which warrants further research.

  8. Novel tilt-curvature coupling in lipid membranes

    Science.gov (United States)

    Terzi, M. Mert; Deserno, Markus

    2017-08-01

    On mesoscopic scales, lipid membranes are well described by continuum theories whose main ingredients are the curvature of a membrane's reference surface and the tilt of its lipid constituents. In particular, Hamm and Kozlov [Eur. Phys. J. E 3, 323 (2000)] have shown how to systematically derive such a tilt-curvature Hamiltonian based on the elementary assumption of a thin fluid elastic sheet experiencing internal lateral pre-stress. Performing a dimensional reduction, they not only derive the basic form of the effective surface Hamiltonian but also express its emergent elastic couplings as trans-membrane moments of lower-level material parameters. In the present paper, we argue, though, that their derivation unfortunately missed a coupling term between curvature and tilt. This term arises because, as one moves along the membrane, the curvature-induced change of transverse distances contributes to the area strain—an effect that was believed to be small but nevertheless ends up contributing at the same (quadratic) order as all other terms in their Hamiltonian. We illustrate the consequences of this amendment by deriving the monolayer and bilayer Euler-Lagrange equations for the tilt, as well as the power spectra of shape, tilt, and director fluctuations. A particularly curious aspect of our new term is that its associated coupling constant is the second moment of the lipid monolayer's lateral stress profile—which within this framework is equal to the monolayer Gaussian curvature modulus, κ¯ m. On the one hand, this implies that many theoretical predictions now contain a parameter that is poorly known (because the Gauss-Bonnet theorem limits access to the integrated Gaussian curvature); on the other hand, the appearance of κ¯ m outside of its Gaussian curvature provenance opens opportunities for measuring it by more conventional means, for instance by monitoring a membrane's undulation spectrum at short scales.

  9. Bioactive Structure of Membrane Lipids and Natural Products Elucidated by a Chemistry-Based Approach.

    Science.gov (United States)

    Murata, Michio; Sugiyama, Shigeru; Matsuoka, Shigeru; Matsumori, Nobuaki

    2015-08-01

    Determining the bioactive structure of membrane lipids is a new concept, which aims to examine the functions of lipids with respect to their three-dimensional structures. As lipids are dynamic by nature, their "structure" does not refer solely to a static picture but also to the local and global motions of the lipid molecules. We consider that interactions with lipids, which are completely defined by their structures, are controlled by the chemical, functional, and conformational matching between lipids and between lipid and protein. In this review, we describe recent advances in understanding the bioactive structures of membrane lipids bound to proteins and related molecules, including some of our recent results. By examining recent works on lipid-raft-related molecules, lipid-protein interactions, and membrane-active natural products, we discuss current perspectives on membrane structural biology. © 2015 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Oxidative Stress Induced Lipid Peroxidation And DNA Adduct Formation In The Pathogenesis Of Multiple Myeloma And Lymphoma

    Directory of Open Access Journals (Sweden)

    Tandon, Ravi

    2013-02-01

    Full Text Available Objective: To access the oxidative stress status by quantification of byproducts generated during lipid peroxidation and DNA breakdown products generated during DNA damage in the blood serum of multiple myeloma and lymphoma patients.Material & Methods: Case control study comprised of 40 patients of multiple myeloma and 20 patients of lymphoma along with 20 age and sex-matched healthy subjects as controls. Levels of Malondialdehyde and 8-hydroxy-2-deoxy-Guanosine were measured to study the oxidative stress status in the study subjects.Results: The level of markers of DNA damage and lipid peroxidation were found to be raised significantly in the study subjects in comparison to healthy controls. The results indicate oxidative stress and DNA damage activity increase progressively with the progression of disease.Conclusion: Oxidative stress causes DNA damage and Lipid peroxidation which results in the formation of DNA adducts leading to mutations thereby indicate the role of oxidative stress in the pathogenesis of multiple myeloma and lymphoma.

  11. Antioxidant properties of aqueous extracts of unripe Musa paradisiaca on sodium nitroprusside induced lipid peroxidation in rat pancreas in vitro

    Science.gov (United States)

    Shodehinde, Sidiqat Adamson; Oboh, Ganiyu

    2013-01-01

    Objective To evaluate and compare antioxidant activities of the aqueous extracts of unripe plantain (Musa paradisiaca), assess their inhibitory action on sodium nitroprusside induced lipid peroxidation in rat pancreas in vitro and to characterize the main phenolic constituents of the plantain products using gas chromatography analysis. Methods Aqueous extracts of plantain products (raw, elastic pastry, roasted and boiled) flour of 0.1 g/mL (each) were used to determine their total phenol, total flavonoid, 1,1 diphenyl-2 picrylhydrazyl (DPPH) and hydroxyl (OH) radical scavenging ability. The inhibitory effect of the extracts on sodium nitroprusside induced lipid peroxidation was also determined. Results The results revealed that all the aqueous extracts showed antioxidant activity. The boiled flour had highest DPPH and OH radical scavenging ability while raw flour had the highest Fe2+ chelating ability, sodium nitroprusside inhibitory effect and vitamin C content. The antioxidant results showed that elastic pastry had the highest total phenol and total flavonoid content. Characterization of the unripe plantain products for polyphenol contents using gas chromatography showed varied quantity of apigenin, myricetin, luteolin, capsaicin, isorhaemnetin, caffeic acid, kampferol, quercetin, p-hydroxybenzoic acid, shogaol, glycitein and gingerol per product on the spectra. Conclusions Considering the antioxidant activities and ability to inhibit lipid peroxidation of unripe plantain, this could justify their traditional use in the management/prevention of diseases related to stress. PMID:23730557

  12. Water extractable phytochemicals from Capsicum pubescens (tree pepper) inhibit lipid peroxidation induced by different pro-oxidant agents in brain

    International Nuclear Information System (INIS)

    Oboh, G.; Rocha, J.B.T.

    2006-03-01

    Reactive oxygen species (ROS) is the cause of neurodegenerative disorders such as Lou Gehrig's disease, Parkinson's disease and Huntington's disease; one practical way to prevent and manage neurodegenerative diseases is through the eating of food rich in antioxidants (dietary means). In this study, the antioxidant and neuroprotective properties of aqueous extract of ripe and unripe Capsicum pubescens (popularly known as tree pepper) on different pro-oxidant induced lipid peroxidation in Rat's brain (in vitro) is been investigated. Aqueous extract of freshly harvested pepper was prepared, and the total phenol content, vitamin C, ferric reducing antioxidant property (FRAP) and Fe (II) chelating ability was determined. In addition, the ability of the extracts to protect the Rat's brain against some pro-oxidant FeSO 4 , Sodium nitroprusside and Quinolinic acid) - induced oxidative stress was also determined. The results of the study revealed that ripe Capsicum pubescens had a significantly higher (P 2 O 2 induced decomposition of deoxyribose. Therefore, ripe and unripe Capsicum pubescens would inhibit lipid peroxidation in vitro. However, the ripe potent was a more potent inhibitor of lipid peroxidation, which is probably due to its higher vitamin C and phenol content, reducing power and Fe (II) chelating ability. (author)

  13. Antioxidant properties of aqueous extracts of unripe Musa paradisiaca on sodium nitroprusside induced lipid peroxidation in rat pancreas in vitro.

    Science.gov (United States)

    Shodehinde, Sidiqat Adamson; Oboh, Ganiyu

    2013-06-01

    To evaluate and compare antioxidant activities of the aqueous extracts of unripe plantain (Musa paradisiaca), assess their inhibitory action on sodium nitroprusside induced lipid peroxidation in rat pancreas in vitro and to characterize the main phenolic constituents of the plantain products using gas chromatography analysis. Aqueous extracts of plantain products (raw, elastic pastry, roasted and boiled) flour of 0.1 g/mL (each) were used to determine their total phenol, total flavonoid, 1,1 diphenyl-2 picrylhydrazyl (DPPH) and hydroxyl (OH) radical scavenging ability. The inhibitory effect of the extracts on sodium nitroprusside induced lipid peroxidation was also determined. The results revealed that all the aqueous extracts showed antioxidant activity. The boiled flour had highest DPPH and OH radical scavenging ability while raw flour had the highest Fe(2+) chelating ability, sodium nitroprusside inhibitory effect and vitamin C content. The antioxidant results showed that elastic pastry had the highest total phenol and total flavonoid content. Characterization of the unripe plantain products for polyphenol contents using gas chromatography showed varied quantity of apigenin, myricetin, luteolin, capsaicin, isorhaemnetin, caffeic acid, kampferol, quercetin, p-hydroxybenzoic acid, shogaol, glycitein and gingerol per product on the spectra. Considering the antioxidant activities and ability to inhibit lipid peroxidation of unripe plantain, this could justify their traditional use in the management/prevention of diseases related to stress.

  14. Effects of chilled storage and cryopreservation on sperm characteristics, antioxidant enzyme activities, and lipid peroxidation in Pacific cod Gadus microcephalus

    Science.gov (United States)

    Wang, Xueying; Shi, Xuehui; Liu, Yifan; Yu, Daode; Guan, Shuguang; Liu, Qinghua; Li, Jun

    2016-07-01

    The present study evaluated the effects of chilled storage and cryopreservation on sperm motion characteristics, antioxidant enzyme activities, and lipid peroxidation in the Pacific cod Gadus macrocephalus. Sperm motility and the activities of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (Gr), and lipid peroxidation (measured via malondialdehyde (MDA) content) were determined after the milt was stored at 4°C for 12 h, cryopreserved without cryoprotectant in 12% propylene glycol (PG), cryopreserved in 12% PG+0.1 mol/L trehalose, or cryopreserved in 12% PG spermatozoa but centrifuged to decant the supernatant prior to cryopreservation (only sperm cells were cryopreserved). After chilled storage or cryopreservation, the SOD, CAT and GPx activities were reduced in sperm cells and increased in seminal plasma in almost all treatments; sperm motility parameters were also decreased. However, the addition of trehalose into the cryoprotectant could significantly improve the postthaw sperm quality as revealed by the sperm average path velocity. This improvement might be attributed to the function of trehalose in scavenging reactive oxygen species. Chilled storage and cryopreservation had significant effects on sperm motion characteristics, antioxidant enzyme activities, and lipid peroxidation in the Pacific cod.

  15. Lipolysis, lipid peroxidation, and color characteristics of Serrano Hams from Duroc and large white pigs during dry-curing.

    Science.gov (United States)

    del Olmo, Ana; Calzada, Javier; Nuñez, Manuel

    2013-11-01

    Lipolysis, lipid peroxidation, and colorimetric characteristics of Serrano hams from Duroc and Large White pigs along a 15-mo curing period were investigated. Physicochemical parameters of both types of hams evolved similarly during curing. Twelve of 13 free fatty acids (FFAs) increased during curing, eicosatrienoic acid being the only exception. Linoleic, stearic, and arachidonic acids and the minor heptadecanoic acid reached lower concentrations, and the rest of minor FFAs higher concentrations, in Duroc hams than in Large White hams. The index measuring the early stage of lipid peroxidation declined from month 5 onwards, indicating that the phenomenon had been completed by month 5, while the index of the secondary stage of lipid peroxidation increased with curing time. Higher values were found for the 1st index in Duroc hams. Curing affected color parameters. Lightness decreased and redness increased in both types of hams, while yellowness decreased only in Duroc hams. Lower redness values were found for Duroc hams. Major differences in color parameters were found between muscles. Principal components analysis of FFAs yielded 2 main principal components. The 1st factor, correlated with all FFAs excepting eicosatrienoic acid, allowed discrimination between curing times. The 2nd factor, correlated with eicosatrienoic acid, permitted discrimination between breeds. © 2013 Institute of Food Technologists®

  16. Digestibility of Quinoa (Chenopodium quinoa Willd.) Protein Concentrate and Its Potential to Inhibit Lipid Peroxidation in the Zebrafish Larvae Model.

    Science.gov (United States)

    Vilcacundo, R; Barrio, D; Carpio, C; García-Ruiz, A; Rúales, J; Hernández-Ledesma, B; Carrillo, W

    2017-09-01

    Quinoa protein concentrate (QPC) was extracted and digested under in vitro gastrointestinal conditions. The protein content of QPC was in the range between 52.40 and 65.01% depending on the assay used. Quinoa proteins were almost completely hydrolyzed by pepsin at pH of 1.2, 2.0, and 3.2. At high pH, only partial hydrolysis was observed. During the duodenal phase, no intact proteins were visible, indicating their susceptibility to the in vitro simulated digestive conditions. Zebrafish larvae model was used to evaluate the in vivo ability of gastrointestinal digests to inhibit lipid peroxidation. Gastric digestion at pH 1.2 showed the highest lipid peroxidation inhibition percentage (75.15%). The lipid peroxidation activity increased after the duodenal phase. The digest obtained at the end of the digestive process showed an inhibition percentage of 82.10%, comparable to that showed when using BHT as positive control (87.13%).

  17. Higher lipid peroxidation in former-smokers vs. never-smokers - study in postmenopausal women.

    Science.gov (United States)

    Sagan, Dorota; Stępniak, Jan; Gesing, Adam; Lewinski, Andrzej; Karbownik-Lewinska, Malgorzata

    2015-12-01

    One of the most spectacular exogenous prooxidative agents is cigarette smoking, constituting a well documented risk factor for several diseases. In turn it is suggested that hormone replacement therapy (HRT) in postmenopausal women can contribute to oxidative status. The aim of the study was to evaluate the level of oxidative damage to membrane lipids in blood serum collected from never-smokers and former-smokers. The study was performed in postmenopausal women, who were or were not HRT users. Ninety (90) female volunteers, aged from 46 to 67 years, were enrolled. Two major groups were considered, i.e. never-smokers (n=44) and formersmokers (n=46), which were additionally subgrouped to HRT users (HRT+) and HRT non-users (HRT-). Anthropometric parameters related to obesity were also calculated. The main groups were well matched at baseline in terms of age. The level of malondialdehyde+4-hydroxyalkenals (MDA+4-HDA), as the index of LPO, was measured spectrophotometrically. The level of LPO was higher in former-smokers than in never-smokers, regardless of HRT use. The level of LPO did constitute the only independent factor associated with past smoking in the entire examined group, as well as after stratification to HRT users and HRT non-users. LPO level was not associated with HRT treatment. No positive correlations were found between LPO level and anthropometric parameters. Past smoking is independently associated with the increased damage to membrane lipids regardless of the use of HRT in postmenopausal women. Smoking cessation is not always associated with complete reversion of excessive oxidative damage to all biological macromolecules.

  18. Elasto-plasticity in wrinkled polymerized lipid membranes

    KAUST Repository

    Chaieb, Sahraoui

    2014-01-15

    Biomembranes shown to behave like elastic sheets, can also suffer plastic deformations. Neutron scattering experiments on partially polymerised wrinkled membranes revealed that when a critical degree of polymerisation is crossed, the wrinkled membranes do not resume their spherical shapes. Instead they remain wrinkled and rigid while their non-polymerised counterparts resume their spherical floppy shapes. The yield stress of these membranes, measured for the first time via the fractal dimension, is intimately related to the degree of polymerisation probably through a 2D disorder that quenches the lateral diffusion of the lipid molecules. This work might shed light on the physical reason behind the irreversible deformation of echinocytes, acanthocytes and malaria infected red blood cells.

  19. Elasto-plasticity in wrinkled polymerized lipid membranes

    KAUST Repository

    Chaieb, Saharoui

    2014-01-01

    Biomembranes shown to behave like elastic sheets, can also suffer plastic deformations. Neutron scattering experiments on partially polymerised wrinkled membranes revealed that when a critical degree of polymerisation is crossed, the wrinkled membranes do not resume their spherical shapes. Instead they remain wrinkled and rigid while their non-polymerised counterparts resume their spherical floppy shapes. The yield stress of these membranes, measured for the first time via the fractal dimension, is intimately related to the degree of polymerisation probably through a 2D disorder that quenches the lateral diffusion of the lipid molecules. This work might shed light on the physical reason behind the irreversible deformation of echinocytes, acanthocytes and malaria infected red blood cells.

  20. Evaluation of antioxidant capacity and membrane stabilizing ...

    African Journals Online (AJOL)

    Both the leaf and root of C. adenocaulis were extracted with 70% ethanol to yield the ... ELE and ERE were able to protect red blood cell (RBC) membrane against ... antioxidant, anti-inflammatory, lipid peroxidation, membrane stabilization.

  1. Dietary docosahexaenoic acid-induced generation of liver lipid peroxides is not suppressed further by elevated levels of glutathione in ODS rats.

    Science.gov (United States)

    Sekine, Seiji; Kubo, Kazuhiro; Tadokoro, Tadahiro; Saito, Morio

    2006-04-01

    We examined the effects of ascorbic acid (AsA) and glutathione (GSH; experiment 1) and of GSH in acetaminophen-fed rats (experiment 2) on dietary docosahexaenoic acid (DHA)-induced tissue lipid peroxidation. In experiment 1, AsA-requiring Osteogenic Disorder Shionogi/Shi-od/od (ODS) rats were fed soybean protein diets containing DHA (10.0% total energy) and AsA at 50 (low) or 300 (normal) mg/kg without (low) or with (normal) methionine at 2 g/kg for 32 d. In experiment 2, ODS rats were fed diets containing DHA (7.8% total energy) and acetaminophen (4 g/kg) with different levels of dietary methionine (low, moderate, high, and excessive at 0, 3, 6, and 9 g/kg, respectively) for 30 d. Tissue lipid peroxides and antioxidant levels were determined. In experiment 1, liver lipid peroxide levels in the low-AsA group were lower than those in the normal-AsA group, but kidney and testis lipid peroxide levels in the low-AsA group were higher than those in the normal-AsA group. Dietary methionine tended to decrease tissue lipid peroxide levels but did not decrease vitamin E (VE) consumption. In experiment 2, a high level of methionine (6 g/kg) decreased liver lipid peroxide levels and VE consumption. However, generation of tissue lipid peroxides and VE consumption were not decreased further by a higher dose of methionine (9 g/kg). Higher than normal levels of dietary methionine are not necessarily associated with decreased dietary DHA-induced generation of tissue lipid peroxides and VE consumption except that the GSH requirement is increased in a condition such as acetaminophen feeding.

  2. Effects of dietary [alpha]-tocopherol and [beta]-carotene on lipid peroxidation induced by methyl mercuric chloride in mice

    Energy Technology Data Exchange (ETDEWEB)

    Raun Andersen, H; Andersen, O [Department of Environmental Medicine, University of Odense, Odense (Denmark)

    1993-01-01

    Exposure of male CBA mice to methyl mercuric chloride, CH[sub 3]HgCl, (10-40 mg/l in drinking water) for 2 weeks resulted in dose-related Hg deposition and enhanced lipid peroxidation in liver, kidney and brain. Mice were fed well-defined semisynthetic diets containing different levels of [alpha]-tocopherol (10, 100 or 1000 mg/kg) or [beta]-carotene (1000, 10,000 or 100,000 IU/kg) for four weeks, two groups on each diet. The concentration of [alpha]-tocopherol and [beta]-carotene used corresponded to deficient, normal and high levels. During the last two weeks, one group on each diet was given 40 mg CH[sub 3]HgCl/l of drinking water. High dietary [alpha]-tocopherol protected against CH[sub 3]HgCl induced hepatic lipid peroxidation, whereas the [alpha]-tocopherol deficient diet further enhanced CH[sub 3]HgCl induced hepatic lipid peroxidation. Similar, though statistically non-significant effects occurred in the kidneys, [alpha]-tocopherol did not protect against CH[sub 3]HgCl induced lipid peroxidation in the brain. Excess dietary [beta]-carotene further enhanced CH[sub 3]HgCl induced lipid peroxidation in liver, kidney and brain. CH[sub 3]HgCl significantly decreased the activity of total glutathione peroxidase (T-GSH-Px) and Se-dependent glutathione peroxidase (Se-GSH-Px) in the kidneys in all dietary groups. High dietary [alpha]-tocopherol enhanced the activity of Se-GSH-Px in liver and kidney compared to the activity in mice fed the normal level of [alpha]-tocopherol. This occurred in mice exposed to CH[sub 3]-HgCl as well as in unexposed mice, and the difference between CH[sub 3]HgCl exposed and unexposed mice was not diminished. High dietary [alpha]-tocopherol increased the activity of both Se-GSH-Px and T-GSH-Px in the brain of CH[sub 3]HgCl-exposed mice. The dietary level of [beta]-carotene did not affect the activity of the two enzymes in the organs investigated. (au) (43 refs.).

  3. Effects of dietary α-tocopherol and β-carotene on lipid peroxidation induced by methyl mercuric chloride in mice

    International Nuclear Information System (INIS)

    Raun Andersen, H.; Andersen, O.

    1993-01-01

    Exposure of male CBA mice to methyl mercuric chloride, CH 3 HgCl, (10-40 mg/l in drinking water) for 2 weeks resulted in dose-related Hg deposition and enhanced lipid peroxidation in liver, kidney and brain. Mice were fed well-defined semisynthetic diets containing different levels of α-tocopherol (10, 100 or 1000 mg/kg) or β-carotene (1000, 10,000 or 100,000 IU/kg) for four weeks, two groups on each diet. The concentration of α-tocopherol and β-carotene used corresponded to deficient, normal and high levels. During the last two weeks, one group on each diet was given 40 mg CH 3 HgCl/l of drinking water. High dietary α-tocopherol protected against CH 3 HgCl induced hepatic lipid peroxidation, whereas the α-tocopherol deficient diet further enhanced CH 3 HgCl induced hepatic lipid peroxidation. Similar, though statistically non-significant effects occurred in the kidneys, α-tocopherol did not protect against CH 3 HgCl induced lipid peroxidation in the brain. Excess dietary β-carotene further enhanced CH 3 HgCl induced lipid peroxidation in liver, kidney and brain. CH 3 HgCl significantly decreased the activity of total glutathione peroxidase (T-GSH-Px) and Se-dependent glutathione peroxidase (Se-GSH-Px) in the kidneys in all dietary groups. High dietary α-tocopherol enhanced the activity of Se-GSH-Px in liver and kidney compared to the activity in mice fed the normal level of α-tocopherol. This occurred in mice exposed to CH 3 -HgCl as well as in unexposed mice, and the difference between CH 3 HgCl exposed and unexposed mice was not diminished. High dietary α-tocopherol increased the activity of both Se-GSH-Px and T-GSH-Px in the brain of CH 3 HgCl-exposed mice. The dietary level of β-carotene did not affect the activity of the two enzymes in the organs investigated. (au) (43 refs.)

  4. Dietary antioxidants, lipid peroxidation and plumage colouration in nestling blue tits Cyanistes caeruleus

    Science.gov (United States)

    Larcombe, Stephen D.; Mullen, William; Alexander, Lucille; Arnold, Kathryn E.

    2010-10-01

    Carotenoid pigments are responsible for many of the red, yellow and orange plumage and integument traits seen in birds. One idea suggests that since carotenoids can act as antioxidants, carotenoid-mediated colouration may reveal an individual's ability to resist oxidative damage. In fact, there is currently very little information on the effects of most dietary-acquired antioxidants on oxidative stress in wild birds. Here, we assessed the impacts on oxidative damage, plasma antioxidants, growth and plumage colouration after supplementing nestling blue tits Cyanistes caeruleus with one of three diets; control, carotenoid treatment or α-tocopherol treatment. Oxidative damage was assessed by HPLC analysis of plasma levels of malondialdehyde (MDA), a by-product of lipid peroxidation. Contrary to predictions, we found no differences in oxidative damage, plumage colouration or growth rate between treatment groups. Although plasma lutein concentrations were significantly raised in carotenoid-fed chicks, α-tocopherol treatment had no effect on concentrations of plasma α-tocopherol compared with controls. Interestingly, we found that faster growing chicks had higher levels of oxidative damage than slower growing birds, independent of treatment, body mass and condition at fledging. Moreover, the chromatic signal of the chest plumage of birds was positively correlated with levels of MDA but not plasma antioxidant concentrations: more colourful nestlings had higher oxidative damage than less colourful individuals. Thus, increased carotenoid-mediated plumage does not reveal resistance to oxidative damage for nestling blue tits, but may indicate costs paid, in terms of oxidative damage. Our results indicate that the trade-offs between competing physiological systems for dietary antioxidants are likely to be complex in rapidly developing birds. Moreover, interpreting the biological relevance of different biomarkers of antioxidant status represents a challenge for evolutionary

  5. The effects of dexketoprofen on endogenous leptin and lipid peroxidation during liver ischemia reperfusion injury.

    Science.gov (United States)

    Ustun, Yasemin Burcu; Koksal, Ersin; Kaya, Cengiz; Sener, Elif Bengi; Aksoy, Abdurrahman; Yarim, Gul; Kabak, Yonca; Gulbahar, Yavuz

    2014-01-01

    Hepatic ischemia reperfusion (IR) injury has complex mechanisms. We investigated the effect of dexketoprofen on endogenous leptin and malondialdehyde (MDA) levels. Wistar albino rats were divided into 4 equal groups and were subjected to 1-hour ischemia and different subsequent reperfusion intervals. Dexketoprofen was administered in a dose of 25 mg/kg 15 minutes before ischemia induction and 1-hour reperfusion to the Dexketoprofen one-hour reperfusion group, n = 6 (DIR1) group and 6-hour reperfusion to the Dexketoprofen six-hour reperfusion group, n = 6 (DIR6) group. In the control groups, 0.9% physiologic serum (SF) was administered 15 minutes before ischemia induction and 1-hour reperfusion to the one-hour reperfusion group, n = 6 (IR1) group and 6-hour reperfusion to the six-hour reperfusion group, n = 6 (IR6) group. Although serum leptin (P = 0.044) and hepatic tissue MDA levels (P = 0.004) were significantly higher in the IR6 group than in the IR1 group, there were no significant differences in dexketoprofen pretreatment between the DIR1 and DIR6 groups. There were no differences in serum MDA levels among the 4 groups, and serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities were significantly higher in the IR1 (P = 0.026 and P = 0.018, respectively) and IR6 (P = 0.000 and P = 0.002, respectively) groups than in the DIR1 and DIR6 groups. Dexketoprofen pretreatment can protect the liver from IR injury by decreasing inflammation and lipid peroxidation. Our study shows that dexketoprofen has no effects on endogenous leptin during IR injury.

  6. Lipid peroxidation in microsomes of murine bone marrow after low-dose γ-irradiation

    International Nuclear Information System (INIS)

    Schwenke, K.; Coslar, S.; Muehlensiepen, H.; Altman, K.I.; Feinendegen, L.E.

    1994-01-01

    The principal aim of the study was to investigate the effect of low-dose γ-irradiation on lipid peroxidation (LPO) in murine bone marrow. To this end, the degree of LPO in suspensions of microsomes of murine bone marrow cells (BMC) was determined in terms of malondialdehyde (MDA) formation after whole-body or in vitro exposure to various doses of γ-radiation. These effects were compared to some extent with similar effects in liver and spleen preparations. As to the effect of γ-irradiation on LPO in BMC, the response depends on the dose level and on whether whole-body or in vitro exposures are involved. Whole-body irradiation did not result in an increase in LPO in BMC microsomes, even at such high doses as 15 Gy, although hepatic microsomes showed a marked increase. In contrast, in vitro irradiation of BMC microsomes with 0.1, 10 and 50 Gy brought about an increase in LPO. This increase was already significant (P < 0.05) at 0.1 Gy following a post-irradiation incubation and substantial at 50 Gy, even without subsequent incubation. The results show that low doses of γ-irradiation are able to induce an elevation of LPO in murine BMC microsomes, but only after in vitro irradiation. In the case of whole-body irradiation cellular radical scavengers and other metabolic reactions may prevent a measurable increase in LPO. This is partly illustrated by the case of vitamin-E deficiency, where a substantial increase in LPO in BMC microsomes is observed even without γ-irradiation in comparison with euvitaminotic mice because normally occurring radicals are not scavenged sufficiently. (orig.)

  7. Lipid peroxidation and antioxidants status in human malignant and non-malignant thyroid tumours.

    Science.gov (United States)

    Stanley, J A; Neelamohan, R; Suthagar, E; Vengatesh, G; Jayakumar, J; Chandrasekaran, M; Banu, S K; Aruldhas, M M

    2016-06-01

    Thyroid epithelial cells produce moderate amounts of reactive oxygen species that are physiologically required for thyroid hormone synthesis. Nevertheless, when they are produced in excessive amounts, they may become toxic. The present study is aimed to compare the lipid peroxidation (LPO), antioxidant enzymes - superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and non-protein thiols (reduced glutathione (GSH)) in human thyroid tissues with malignant and non-malignant disorders. The study used human thyroid tissues and blood samples from 157 women (147 diseased and 10 normal). Thyroid hormones, oxidative stress markers and antioxidants were estimated by standard methods. LPO significantly increased in most of the papillary thyroid carcinoma (PTC: 82.9%) and follicular thyroid adenoma (FTA: 72.9%) tissues, whilst in a majority of nodular goitre (69.2%) and Hashimoto's thyroiditis (HT: 73.7%) thyroid tissues, it remained unaltered. GSH increased in PTC (55.3%), remained unaltered in FTA (97.3%) and all other goiter samples studied. SOD increased in PTC (51.1%) and all other malignant thyroid tissues studied. CAT remained unaltered in PTC (95.7%), FTA (97.3%) and all other non-malignant samples (HT, MNG, TMNG) studied. GPx increased in PTC (63.8%), all other malignant thyroid tissues and remained unaltered in many of the FTA (91.9%) tissues and all other non-malignant samples (HT, MNG, TMNG) studied. In the case of non-malignant thyroid tumours, the oxidant-antioxidant balance was undisturbed, whilst in malignant tumours the balance was altered, and the change in r value observed in the LPO and SOD pairs between normal and PTC tissues and also in many pairs with multi-nodular goitre (MNG)/toxic MNG tissues may be used as a marker to differentiate/detect different malignant/non-malignant thyroid tumours. © The Author(s) 2015.

  8. Assessment of lipid and protein peroxidation markers in non-pregnant and pregnant female dogs.

    Science.gov (United States)

    Szczubiał, M; Kankofer, M; Dąbrowski, R; Bochniarz, M; Urban-Chmiel, R

    2015-01-01

    The aim of the study was to investigate oxidative stress during normal pregnancy in female dogs based on an evaluation of plasma markers for lipid and protein peroxidation. Twenty clinically healthy female dogs (10 non-pregnant and 10 pregnant) were used in the study. Blood samples from the pregnant animals were collected at 19-21, 38-40, and 56-58 days of pregnancy. Blood samples from non-pregnant female dogs were obtained between 20 and 35 days after ineffective breeding. As indicators of oxidative stress, we measured the following using spectrophotometric and spectrof- luorimetric methods: thiobarbituric acid reactive substances (TBARS), radical cations of N,N, diethylparaphenylene diamine (RC-DEPPD), sulfhydryl groups (SH groups), bityrosine and formylkynurenine. The mean plasma TBARS concentration in the pregnant dogs (0.486 ± 0.071-0.581 ± 0.191 μmol/g protein) was significantly higher (p pregnant animals (0.274 ± 0.111 μmol/g protein). A marked, although not significant, decrease in SH group content, as well as an increase in bityrosine and formylkynurenine concentration were concurrently observed in the pregnant dogs. No significant differences were found in terms of the studied markers in the pregnant animals when comparing the values obtained during the investigated periods of pregnancy, although there was a progressive decrease in TBARS concentration and a progressive increase in RC-DEPPD, bityrosine and formylkynurenine contents. Our findings suggest that normal pregnancy in female dogs is associated with oxidative stress. Further studies are necessary to establish the physiological ranges of antioxidative/oxidative profiles in pregnant dogs and to explain if and how the intensity of oxidative stress might contribute to the risk of the complications of pregnancy.

  9. Exhaled ethane: an in vivo biomarker of lipid peroxidation in interstitial lung diseases.

    Science.gov (United States)

    Kanoh, Soichiro; Kobayashi, Hideo; Motoyoshi, Kazuo

    2005-10-01

    Oxidative stress plays a role in the pathogenesis and progression of interstitial lung disease (ILD). Exhaled ethane is a product of lipid peroxidation that has been proposed as a biomarker of oxidative stress in vivo. To determine whether the exhaled ethane level is elevated in patients with ILD and to compare it with other clinical parameters. Breath samples were collected from 34 patients with ILD, including 13 with idiopathic pulmonary fibrosis (IPF), 9 patients with cryptogenic organizing pneumonia, 6 patients with collagen vascular disease-associated interstitial pneumonia, and 6 patients with pulmonary sarcoidosis. Gas samples were obtained at hospital admission and after 3 weeks. After each expired sample was concentrated using a trap-and-purge procedure, the ethane level was analyzed by gas chromatography. Exhaled ethane levels were elevated in ILD patients (n = 34, mean +/- SD, 8.5 +/- 8.0 pmol/dL) compared with healthy volunteers (n = 16, 2.9 +/- 1.0 pmol/dL; p ethane levels were largely consistent with the clinical course. Four patients with IPF who had persistently high ethane levels died or deteriorated, whereas those with ethane levels ethane concentrations were positively correlated with levels of lactate dehydrogenase (Spearman rank correlation coefficient [rs], 0.28, p = 0.026) and C-reactive protein (rs, 0.38, p = 0.025) and were inversely correlated with Pa(O2) (rs, - 0.40, p = 0.0026). Patients showing increased uptake on (67)Ga scintigraphy demonstrated higher ethane levels (n = 19, 7.5 +/- 5.7 pmol/dL) compared with those who did not show increased uptake on scintigraphy (n = 10, 3.0 +/- 2.4 pmol/dL; p ethane is elevated in patients with ILD and is correlated with the clinical outcome, suggesting that it provides useful information about ongoing oxidative stress, and thereby disease activity and severity in ILD.

  10. DNA damage by lipid peroxidation products: implications in cancer, inflammation and autoimmunity

    Directory of Open Access Journals (Sweden)

    Fabrizio Gentile

    2017-04-01

    Full Text Available Oxidative stress and lipid peroxidation (LPO induced by inflammation, excess metal storage and excess caloric intake cause generalized DNA damage, producing genotoxic and mutagenic effects. The consequent deregulation of cell homeostasis is implicated in the pathogenesis of a number of malignancies and degenerative diseases. Reactive aldehydes produced by LPO, such as malondialdehyde, acrolein, crotonaldehyde and 4-hydroxy-2-nonenal, react with DNA bases, generating promutagenic exocyclic DNA adducts, which likely contribute to the mutagenic and carcinogenic effects associated with oxidative stress-induced LPO. However, reactive aldehydes, when added to tumor cells, can exert an anticancerous effect. They act, analogously to other chemotherapeutic drugs, by forming DNA adducts and, in this way, they drive the tumor cells toward apoptosis. The aldehyde-DNA adducts, which can be observed during inflammation, play an important role by inducing epigenetic changes which, in turn, can modulate the inflammatory process. The pathogenic role of the adducts formed by the products of LPO with biological macromolecules in the breaking of immunological tolerance to self antigens and in the development of autoimmunity has been supported by a wealth of evidence. The instrumental role of the adducts of reactive LPO products with self protein antigens in the sensitization of autoreactive cells to the respective unmodified proteins and in the intermolecular spreading of the autoimmune responses to aldehyde-modified and native DNA is well documented. In contrast, further investigation is required in order to establish whether the formation of adducts of LPO products with DNA might incite substantial immune responsivity and might be instrumental for the spreading of the immunological responses from aldehyde-modified DNA to native DNA and similarly modified, unmodified and/or structurally analogous self protein antigens, thus leading to autoimmunity.

  11. Salivary Total Antioxidant Capacity and Lipid Peroxidation in Patients with Erosive Oral Lichen Planus

    Directory of Open Access Journals (Sweden)

    Atena Shirzad

    2014-03-01

    Full Text Available Background and aims. Oral lichen planus is a common chronic inflammatory disease of the oral mucosa with malignant potential, pathogenesis of which is not still well known. Free radicals and reactive oxygen species can play an important role in the pathogenesis of oral lichen planus. The aim of this study was to investigate salivary oxidative stress and antioxidant systems in patients with oral lichen planus. Materials and methods. In this case-control study, 30 patients with oral lichen planus (case group and 30 age- and gender-matched healthy subjects (control group, referring to Dental School of Babol University of Medical Sciences, were selected using simple sampling method. Unstimulated saliva of the two groups was collected. Salivary total antioxidant capacity (TAC and lipid peroxidation products were investigated and compared, using ferric reducing antioxidant power (FRAP and thiobarbituric acid reactive substance (TBARS methods, respectively. Data were analyzed using Student’s ttest. Results. The mean and standard deviation of salivary TAC in patients with oral lichen planus (297.23 ± 149.72 μM was significantly lower than that in the controls (791.43±183.95 μM; P < 0.0001, and mean and standard deviation of salivary malondialdehyde (MDA (0.49 ± 0.30 μM was remarkably higher in oral lichen planus patients compared to the control group (0.15 ± 0.11 μM (P < 0.0001. TAC was also reduced in both groups in line with an increase in the level of MDA (P < 0.0001, r = −0.48. Conclusion. The results of this study suggested that an increase in oxidative stress and an imbalance in antioxidant defense system in the saliva of oral lichen planus patients may be involved in the pathogenesis of oral lichen planus.

  12. Salivary total antioxidant capacity and lipid peroxidation in patients with erosive oral lichen planus.

    Science.gov (United States)

    Shirzad, Atena; Pouramir, Mahdi; Seyedmajidi, Maryam; Jenabian, Niloofar; Bijani, Ali; Motallebnejad, Mina

    2014-01-01

    Background and aims. Oral lichen planus is a common chronic inflammatory disease of the oral mucosa with malignant potential, pathogenesis of which is not still well known. Free radicals and reactive oxygen species can play an important role in the pathogenesis of oral lichen planus. The aim of this study was to investigate salivary oxidative stress and antioxidant systems in patients with oral lichen planus. Materials and methods. In this case-control study, 30 patients with oral lichen planus (case group) and 30 age-and gender-matched healthy subjects (control group), referring to Dental School of Babol University of Medical Sciences, were selected using simple sampling method. Unstimulated saliva of the two groups was collected. Salivary total antioxidant capacity (TAC) and lipid peroxidation products were investigated and compared, using ferric reducing antioxidant power (FRAP) and thiobarbituric acid reactive substance (TBARS) methods, respectively. Data were analyzed using Student' t-test. Results. The mean and standard deviation of salivary TAC in patients with oral lichen planus (297.23 ± 149.72 μM) was significantly lower than that in the controls (791.43 ± 183.95 μM; P & 0.0001), and mean and standard deviation of salivary malondialdehyde (MDA) (0.49 ± 0.30 μM) was remarkably higher in oral lichen planus patients compared to the control group (0.15 ± 0.11 μM) (P & 0.0001). TAC was also reduced in both groups in line with an increase in the level of MDA (P & 0.0001, r = -0.48). Conclusion. The results of this study suggested that an increase in oxidative stress and an imbalance in antioxidant defense system in the saliva of oral lichen planus patients may be involved in the pathogenesis of oral lichen planus.

  13. Glycine reduces tissue lipid peroxidation in hypoxia-reoxygenation-induced necrotizing enterocolitis in rats

    Directory of Open Access Journals (Sweden)

    Meyer Karine Furtado

    2006-01-01

    Full Text Available PURPOSE: To assess the protective effect of glycine in an experimental model of Neonatal Necrotizing Enterocolitis (NEC. METHODS: Fifty (50 neonatal Wistar rats, from a litter of six female rats and weighing 4 to 6 grams, were used. Five animals were cannibalized and the 45 remaining were distributed into three groups: the G1 normal control group (n=12; the G2 Group (n=16, of animals that underwent hypoxia-reoxygenation (HR; the G3 Group of animals (n=17 that underwent HR following a 5% intraperitoneal glycine infusion. The animals underwent hypoxia in a CO2 chamber receiving an air flow of 100% CO2 for 5 minutes and reoxygenation receiving an O2 flow at 100% for 5 minutes. One centimeter long small bowel and colon segments were prepared for histological analysis. The rest of the bowel was removed in a block and frozen at minus 80degreesC for homogenization and determination of tissue malondialdehyde (MDA. Tissue lesions were classified as Grade 0 to Grade 5, according to the level of damaged mucosa. RESULTS: The animals in Group G1 had levels of small bowel and colon lesion significantly smaller as compared to the animals in Groups G2 and G3. The G2 group had mean MDA values significantly higher than the animals in the G1 (p = .015 and G3 (p=0.021 groups. MDA values did not differ significantly (p = 0.992 for the animals in groups G1 and G3. CONCLUSION: Glycine reduces tissue MDA levels (a measurement of lipid peroxidation following HR in neonatal rats.

  14. A new look at lipid-membrane structure in relation to drug research

    DEFF Research Database (Denmark)

    Mouritsen, Ole G.; Jørgensen, Kent

    1998-01-01

    Lipid-bilayer membranes are key objects in drug research in relation to (i) interaction of drugs with membrane-bound receptors, (ii) drug targeting, penetration, and permeation of cell membranes, and (iii) use of liposomes in micro-encapsulation technologies for drug delivery. Rational design...... of new drugs and drug-delivery systems therefore requries insight into the physical properties of lipid-bilayer membranes. This mini-review provides a perspective on the current view of lipid-bilayer structure and dynamics based on information obtained from a variety of recent experimental...... and theoretical studies. Special attention is paid to trans-bilayer structure, lateral molecular organization of the lipid bilayer, lipid-mediated protein assembly, and lipid-bilayer permeability. It is argued that lipids play a major role in lipid membrane-organization and functionality....

  15. Imaging lipid domains in cell membranes: the advent of super-resolution fluorescence microscopy

    Directory of Open Access Journals (Sweden)

    Dylan Myers Owen

    2013-12-01

    Full Text Available The lipid bilayer of model membranes, liposomes reconstituted from cell lipids, and plasma membrane vesicles and spheres can separate into two distinct liquid phases to yield lipid domains with liquid-ordered and liquid-disordered properties. These observations are the basis of the lipid raft hypothesis that postulates the existence of cholesterol-enriched ordered-phase lipid domains in cell membranes that could regulate protein mobility, localization and interaction. Here we review the evidence that nano-scaled lipid complexes and meso-scaled lipid domains exist in cell membranes and how new fluorescence microscopy techniques that overcome the diffraction limit provide new insights into lipid organization in cell membranes.

  16. SAXS investigations on lipid membranes under osmotic stress

    Energy Technology Data Exchange (ETDEWEB)

    Rubim, R.L.; Vieira, V.; Gerbelli, B.B.; Teixeira da Silva, E.R.; Oliveira, C.L.P.; Oliveira, E.A. [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil)

    2012-07-01

    Full text: In this work we, experimentally, investigate the interactions between lipid bilayers. A structural characterization is performed by small angle x-ray scattering (SAXS) on multilamellar systems under known osmotic pressure. Changes in the composition of membranes can modify their mechanical properties and structural parameters, like the flexibility of these membranes, which plays a key role on the determination of the tridimensional organization of bilayers. The membranes are composed of soya lecithin, where the major component is DPPC (Dipalmitoylphosphatidylcholine), and fatty acids are incorporated to the membrane in different concentrations, in order to turn the membrane more fluid. The membranes are inserted in a solution of PVP [poly(vinyl-pyrrolidone) - 40000] and the polymer will apply an osmotic pressure on them. The osmotic pressure is controlled by preparing PVP solutions of desired composition and, as we know the concentration of polymer in solution, we can obtain the intensity of the osmotic pressure. SAXS experiments were done in order to determine the distance between the bilayer. From the position of the Bragg peaks, the lamellar periodicity (the thickness of the membranes plus their distance of separation) was determined. Using theoretical model for the form and structure factors we fitted those experimental data and determined the thickness of the membranes. The distance between the membranes was controlled by the osmotic pressure (P) applied to the membranes and, for a given pressure, we determine the distance between the bilayers (a) on equilibrium. The experimental curve P(a) is theoretically described by the different contributions from van der Waals, hydration and fluctuation forces. From the fitting of experimental curves, relevant parameters characterizing the strength of the different interactions are obtained, such as Hamaker and rigidity constant [2, 3]. We observe that the separation between the bilayers on equilibrium is

  17. Polyphenols of Salix aegyptiaca modulate the activities of drug metabolizing and antioxidant enzymes, and level of lipid peroxidation.

    Science.gov (United States)

    Nauman, Mohd; Kale, R K; Singh, Rana P

    2018-03-07

    Salix aegyptiaca is known for its medicinal properties mainly due to the presence of salicylate compounds. However, it also contains other beneficial phytochemicals such as gallic acid, quercetin, rutin and vanillin. The aim of the study was to examine the redox potential, antioxidant and anti-inflammatory activity of these phytochemicals along with acetylsalicylic acid. The redox potential and antioxidant activity of gallic acid, quercetin, rutin, vanillin and acetylsalicylic acid were determined by oxidation-reduction potential electrode method and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay, respectively. In ex vivo studies, antioxidant activity of these phytochemicals was determined by lipid peroxidation and carbonyl content assay in the liver of mice. Anti-inflammatory activity was determined by protein denaturation method. Six-week old C57BL/6 mice treated with gallic acid (100 mg/kg body weight) and acetylsalicylic acid (25 and 50 mg/kg body weight) to investigate their in vivo modulatory effects on the specific activities of drug metabolizing phase I and phase II enzymes, antioxidant enzymes and level of lipid peroxidation in liver. The order of ability to donate electron and antioxidant activity was found to be: gallic acid > quercetin > rutin > vanillin > acetylsalicylic acid. In ex vivo studies, the similar pattern and magnitude of inhibitory effects of these phytochemicals against peroxidative damage in microsomes and protein carbonyl in cytosolic fraction were observed. In in vivo studies, gallic acid and acetylsalicylic acid alone or in combination, enhanced the specific activities of drug metabolizing phase I and phase II enzymes as well as antioxidant enzymes and also inhibited lipid peroxidation in liver. These findings show a close link between the electron donation and antioxidation potential of these phytochemicals, and in turn their biological activity. Gallic acid, quercetin, rutin and vanillin were found to be better electron donors and

  18. Interaction pathways between soft lipid nanodiscs and plasma membranes: A molecular modeling study.

    Science.gov (United States)

    Li, Shixin; Luo, Zhen; Xu, Yan; Ren, Hao; Deng, Li; Zhang, Xianren; Huang, Fang; Yue, Tongtao

    2017-10-01

    Lipid nanodisc, a model membrane platform originally synthesized for study of membrane proteins, has recently been used as the carrier to deliver amphiphilic drugs into target tumor cells. However, the central question of how cells interact with such emerging nanomaterials remains unclear and deserves our research for both improving the delivery efficiency and reducing the side effect. In this work, a binary lipid nanodisc is designed as the minimum model to investigate its interactions with plasma membranes by using the dissipative particle dynamics method. Three typical interaction pathways, including the membrane attachment with lipid domain exchange of nanodiscs, the partial membrane wrapping with nanodisc vesiculation, and the receptor-mediated endocytosis, are discovered. For the first pathway, the boundary normal lipids acting as ligands diffuse along the nanodisc rim to gather at the membrane interface, repelling the central bola lipids to reach a stable membrane attachment. If bola lipids are positioned at the periphery and act as ligands, they diffuse to form a large aggregate being wrapped by the membrane, leaving the normal lipids exposed on the membrane exterior by assembling into a vesicle. Finally, by setting both central normal lipids and boundary bola lipids as ligands, the receptor-mediated endocytosis occurs via both deformation and self-rotation of the nanodiscs. All above pathways for soft lipid nanodiscs are quite different from those for rigid nanoparticles, which may provide useful guidelines for design of soft lipid nanodiscs in widespread biomedical applications. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. The effect of MLS laser radiation on cell lipid membrane.

    Science.gov (United States)

    Pasternak, Kamila; Wróbel, Dominika; Nowacka, Olga; Pieszyński, Ireneusz; Bryszewska, Maria; Kujawa, Jolanta

    2018-03-14

    Authors of numerous publications have proved the therapeutic effect of laser irradiation on biological material, but the mechanisms at cellular and subcellular level are not yet well understood. The aim of this study was to assess the effect of laser radiation emitted by the MLS M1 system (Multiwave Locked System) at two wavelengths (808 nm continuous and 905 nm pulsed) on the stability and fluidity of liposomes with a lipid composition similar to that of human erythrocyte membrane or made of phosphatidylocholine. Liposomes were exposed to low-energy laser radiation at surface densities 195 mW/cm2 (frequency 1,000 Hz) and 230 mW/cm2 (frequency 2,000 Hz). Different doses of radiation energy in the range 0-15 J were applied. The surface energy density was within the range 0.46 - 4.9 J/cm 2. The fluidity and stability of liposomes subjected to such irradiation changed depending on the parameters of radiation used. Since MLS M1 laser radiation, depending on the parameters used, affects fluidity and stability of liposomes with the lipid content similar to erythrocyte membrane, it may also cause structural and functional changes in cell membranes.

  20. Effect of docosahexaenoic acid and ascorbate on peroxidation of retinal membranes of ODS rats.

    Science.gov (United States)

    Wang, Jin-Ye; Sekine, Seiji; Saito, Morio

    2003-04-01

    Mutant male osteogenic disorder Shionogi (ODS) rats, unable to synthesize ascorbic acid, were fed diets containing a high content of docosahexaenoic acid (DHA) and different amounts of ascorbic acid, to study the effect of DHA on peroxidative susceptibility of the retina and possible antioxidant action of ascorbic acid. ODS rats were fed from 7 weeks of age with diets containing high DHA (6.4% of total energy). A control group received a diet high in linoleic acid. The diets also contained varying amounts of ascorbic acid. Fatty acid compositions and phospholipid hydroperoxides in rod outer segment (ROS) membranes, and retinal ascorbic acid were analyzed. DHA in ROS membranes was significantly increased in rats fed high DHA, compared with the linoleic acid diet. Levels of phospholipid hydroperoxides in the DHA-fed rats were significantly higher than the linoleic acid-fed rats. Ascorbic acid supplementation did not suppress the phospholipid hydroperoxide levels after a high DHA diet, even when the supplement increased the content of retinal ascorbic acid. In conclusion, high DHA feeding induced a marked increase of phospholipid hydroperoxides in ROS membranes of ODS rats. Supplementation of ascorbic acid did not reverse this increase.

  1. An ER protein functionally couples neutral lipid metabolism on lipid droplets to membrane lipid synthesis in the ER.

    Science.gov (United States)

    Markgraf, Daniel F; Klemm, Robin W; Junker, Mirco; Hannibal-Bach, Hans K; Ejsing, Christer S; Rapoport, Tom A

    2014-01-16

    Eukaryotic cells store neutral lipids such as triacylglycerol (TAG) in lipid droplets (LDs). Here, we have addressed how LDs are functionally linked to the endoplasmic reticulum (ER). We show that, in S. cerevisiae, LD growth is sustained by LD-localized enzymes. When LDs grow in early stationary phase, the diacylglycerol acyl-transferase Dga1p moves from the ER to LDs and is responsible for all TAG synthesis from diacylglycerol (DAG). During LD breakdown in early exponential phase, an ER membrane protein (Ice2p) facilitates TAG utilization for membrane-lipid synthesis. Ice2p has a cytosolic domain with affinity for LDs and is required for the efficient utilization of LD-derived DAG in the ER. Ice2p breaks a futile cycle on LDs between TAG degradation and synthesis, promoting the rapid relocalization of Dga1p to the ER. Our results show that Ice2p functionally links LDs with the ER and explain how cells switch neutral lipid metabolism from storage to consumption. Copyright © 2014 The Authors. Published by Elsevier Inc. All rights reserved.

  2. An ER Protein Functionally Couples Neutral Lipid Metabolism on Lipid Droplets to Membrane Lipid Synthesis in the ER

    Directory of Open Access Journals (Sweden)

    Daniel F. Markgraf

    2014-01-01

    Full Text Available Eukaryotic cells store neutral lipids such as triacylglycerol (TAG in lipid droplets (LDs. Here, we have addressed how LDs are functionally linked to the endoplasmic reticulum (ER. We show that, in S. cerevisiae, LD growth is sustained by LD-localized enzymes. When LDs grow in early stationary phase, the diacylglycerol acyl-transferase Dga1p moves from the ER to LDs and is responsible for all TAG synthesis from diacylglycerol (DAG. During LD breakdown in early exponential phase, an ER membrane protein (Ice2p facilitates TAG utilization for membrane-lipid synthesis. Ice2p has a cytosolic domain with affinity for LDs and is required for the efficient utilization of LD-derived DAG in the ER. Ice2p breaks a futile cycle on LDs between TAG degradation and synthesis, promoting the rapid relocalization of Dga1p to the ER. Our results show that Ice2p functionally links LDs with the ER and explain how cells switch neutral lipid metabolism from storage to consumption.

  3. Fractional hereditariness of lipid membranes: Instabilities and linearized evolution.

    Science.gov (United States)

    Deseri, L; Pollaci, P; Zingales, M; Dayal, K

    2016-05-01

    In this work lipid ordering phase changes arising in planar membrane bilayers is investigated both accounting for elasticity alone and for effective viscoelastic response of such assemblies. The mechanical response of such membranes is studied by minimizing the Gibbs free energy which penalizes perturbations of the changes of areal stretch and their gradients only (Deseri and Zurlo, 2013). As material instabilities arise whenever areal stretches characterizing homogeneous configurations lie inside the spinoidal zone of the free energy density, bifurcations from such configurations are shown to occur as oscillatory perturbations of the in-plane displacement. Experimental observations (Espinosa et al., 2011) show a power-law in-plane viscous behavior of lipid structures allowing for an effective viscoelastic behavior of lipid membranes, which falls in the framework of Fractional Hereditariness. A suitable generalization of the variational principle invoked for the elasticity is applied in this case, and the corresponding Euler-Lagrange equation is found together with a set of boundary and initial conditions. Separation of variables allows for showing how Fractional Hereditariness owes bifurcated modes with a larger number of spatial oscillations than the corresponding elastic analog. Indeed, the available range of areal stresses for material instabilities is found to increase with respect to the purely elastic case. Nevertheless, the time evolution of the perturbations solving the Euler-Lagrange equation above exhibits time-decay and the large number of spatial oscillation slowly relaxes, thereby keeping the features of a long-tail type time-response. Copyright © 2015 Elsevier Ltd. All rights reserved.

  4. Lipid Membrane Encapsulation of a 3D DNA Nano Octahedron.

    Science.gov (United States)

    Perrault, Steven D; Shih, William M

    2017-01-01

    Structural DNA nanotechnology methods such as DNA origami allow for the synthesis of highly precise nanometer-scale materials (Rothemund, Nature 440:297-302, 2006; Douglas et al., Nature 459:414-418, 2009). These offer compelling advantages for biomedical applications. Such materials can suffer from structural instability in biological environments due to denaturation and nuclease digestion (Hahn et al., ACS Nano 2014; Perrault and Shih, ACS Nano 8:5132-5140, 2014). Encapsulation of DNA nanostructures in a lipid membrane compartmentalizes them from their environment and prevents denaturation and nuclease digestion (Perrault and Shih, ACS Nano 8:5132-5140, 2014). Here, we describe the encapsulation of a 50 nm DNA nanostructure having the geometry of a wireframe octahedron in a phospholipid membrane containing poly-(ethylene glycol), resulting in biocompatible DNA nanostructures.

  5. Mesoscale organization of domains in the plasma membrane - beyond the lipid raft.

    Science.gov (United States)

    Lu, Stella M; Fairn, Gregory D

    2018-04-01

    The plasma membrane is compartmentalized into several distinct regions or domains, which show a broad diversity in both size and lifetime. The segregation of lipids and membrane proteins is thought to be driven by the lipid composition itself, lipid-protein interactions and diffusional barriers. With regards to the lipid composition, the immiscibility of certain classes of lipids underlies the "lipid raft" concept of plasmalemmal compartmentalization. Historically, lipid rafts have been described as cholesterol and (glyco)sphingolipid-rich regions of the plasma membrane that exist as a liquid-ordered phase that are resistant to extraction with non-ionic detergents. Over the years the interest in lipid rafts grew as did the challenges with studying these nanodomains. The term lipid raft has fallen out of favor with many scientists and instead the terms "membrane raft" or "membrane nanodomain" are preferred as they connote the heterogeneity and dynamic nature of the lipid-protein assemblies. In this article, we will discuss the classical lipid raft hypothesis and its limitations. This review will also discuss alternative models of lipid-protein interactions, annular lipid shells, and larger membrane clusters. We will also discuss the mesoscale organization of plasmalemmal domains including visible structures such as clathrin-coated pits and caveolae.

  6. No Evidence for Spontaneous Lipid Transfer at ER-PM Membrane Contact Sites.

    Science.gov (United States)

    Merklinger, Elisa; Schloetel, Jan-Gero; Spitta, Luis; Thiele, Christoph; Lang, Thorsten

    2016-04-01

    Non-vesicular lipid transport steps play a crucial role in lipid trafficking and potentially include spontaneous exchange. Since membrane contact facilitates this lipid transfer, it is most likely to occur at membrane contact sites (MCS). However, to date it is unknown whether closely attached biological membranes exchange lipids spontaneously. We have set up a system for studying the exchange of lipids at MCS formed between the endoplasmic reticulum (ER) and the plasma membrane. Contact sites were stably anchored and the lipids cholesterol and phosphatidylcholine (PC) were not capable of transferring spontaneously into the opposed bilayer. We conclude that physical contact between two associated biological membranes is not sufficient for transfer of the lipids PC and cholesterol.

  7. Effects of deformability and thermal motion of lipid membrane on electroporation: By molecular dynamics simulations

    KAUST Repository

    Sun, Sheng; Yin, Guangyao; Lee, Yi-Kuen; Wong, Joseph T.Y.; Zhang, Tong-Yi

    2011-01-01

    Effects of mechanical properties and thermal motion of POPE lipid membrane on electroporation were studied by molecular dynamics simulations. Among simulations in which specific atoms of lipids were artificially constrained at their equilibrium

  8. Effect of Amphotericin B antibiotic on the properties of model lipid membrane

    International Nuclear Information System (INIS)

    Kiryakova, S; Dencheva-Zarkova, M; Genova, J

    2014-01-01

    Model membranes formed from natural and synthetic lipids are an interesting object for scientific investigations due to their similarity to biological cell membrane and their simple structure with controlled composition and properties. Amphotericin B is an important polyene antifungal antibiotic, used for treatment of systemic fungal infections. It is known from the literature that the studied antibiotic has a substantial effect on the transmembrane ionic channel structures. When applied to the lipid membranes it has the tendency to create pores and in this way to affect the structure and the properties of the membrane lipid bilayer. In this work the thermally induced shape fluctuations of giant quasi-spherical liposomes have been used to study the influence of polyene antibiotic amphotericin B on the elastic properties of model lipid membranes. It have been shown experimentally that the presence of 3 mol % of AmB in the lipid membrane reduces the bending elasticity of the lipid membrane for both studied cases: pure SOPC membrane and mixed SOPC-Cholesterol membrane. Interaction of the amphotericin B with bilayer lipid membranes containing channels have been studied in this work. Model membranes were self-assembled using the patch-clamp and tip-dip patch clamp technique. We have found that amphotericin B is an ionophore and reduces the resistance of the lipid bilayer

  9. FEATURES OF PEROXIDIZATION OF LIPIDS AND ITS CORRECTION AT THE PATIENTS OF DUODENAL ULCER

    Directory of Open Access Journals (Sweden)

    T. V. Тregub

    2015-05-01

    [2] Odessa National University named I.I. Mechnikov, Odessa, Ukraine   Summary Aim of work. To study influences of mineral concentrate "Vita" on peroxidization of lipids in red corpuscles and plasma of blood for patients by ulcerous  illness of duodenum. Researches passed on the base of different hospitals Odessa during 5. It was inspected 210 patients in age from 18 to 60  that men there was 75,2 %. Conclusions. Thus, application over of mineral concentrate "Vita" brings to the considerable improvement of clinical flow of duodenal ulser, to the improvement of quality of life and peroxidization of lipids reduces for certain, namely - diminishes maintenance of malonic dialdehyde and diene conugates of the nonsaturated fat acids in plasma and red corpuscles of blood for patients of duodenum ulcer on a background normalization of properties. Keywords: duodenal ulcer, peroxidization of lipids, "Vita".   Резюме Цель работы - исследовать влияние минерального концентрата «Вита» на перекисное окисление липидов в эритроцитах и плазме крови у больных язвенной болезнью двенадцатиперстной кишки. Исследования проходили на базе различных больниц г. Одессы в течение 5 лет. Было обследовано 210 больных в возрасте от 18 до 60 лет, из которых мужчин было 75,2 %. Исследовано, что применение минерального концентрата «Вита» приводит к значительному улучшению клинического течения язвенной болезни двенадцатиперстной кишки, улучшению качества жизни и достоверно снижает перекисное окисление липидов, а

  10. Peculiarities of Airway Inflammation and Lipid Peroxidation in the Development of Hyperosmotic Airway Hyperresponsiveness in Patients with Asthma

    Directory of Open Access Journals (Sweden)

    Alexey B. Pirogov

    2016-12-01

    Full Text Available The aim of our study was to evaluate the role of airway cellular inflammation and the lipid peroxidation level in the development of airway hyperresponsiveness (AHR to inhalation of hypertonic saline (IHS. Methods and Results: The study included the estimation of inflammatory-cellular composition, intracellular concentration of myeloperoxidase (MPO in induced sputum (IS, serum levels of lipid hydroperoxides (LHP, ceruloplasmin, and vitamin E in 29 patients with asthma and 12 healthy persons. AHR to IHS was assessed by spirometry after 3-min IHS via ultrasonic nebulizer. Patients with asthma had higher indices of leukocytes destruction and cytolysis intensity with the increased leukocyte count in IS. Maximum values of neutrophils cytolysis intensity and leukocytic MPO were found in IS of the patients with AHR to IHS. After the bronchial provocation, serum concentration of LHP was higher in these patients in comparison with the patients without the AHR and control groups. In addition, patients with asthma had lower level of antioxidants than healthy subjects. Conclusion: Marked inflammation involving MPO-activated leukocytes and intensive lipid peroxidation underlie the excessive airway response to IHS.

  11. Free radical scavenging activity and lipid peroxidation inhibition of Hypericum helianthemoides (spach Boiss

    Directory of Open Access Journals (Sweden)

    Soheila Moein

    2015-06-01

    Full Text Available Antioxidants are compounds that obstruct the oxidation of macromolecules in the body. In general, there are two categories of antioxidants, natural and synthetic. Recently, interest has been increased considerably for obtaining new natural antioxidants. In this study, the scavenging of free radicals such as DPPH, NO and OH by Hypericum helianthemoides extract was evaluated. Also, the antioxidant properties of this extract were evaluated by FRAP, FTC methods and determination phenolic compounds. The plant was collected from north of Fars Province and plant extraction was obtained using ethanol. In DPPH radical scavenging, different concentrations of the Hypericum extract were added to DPPH radical. In hydroxyl radical scavenging, Fenton reaction mixture, TCA and TBA were mixed with Hypericum extract. In nitric radical scavenging, nitropruside was mixed with Hypericum extract and then sulphanilic acid, naphthylene diamine were added. In determination of phenolic compounds, Folin-ciocalteu and sodium carbonate were added to Hypericum extract. In DPPH radical scavenging, the IC50 of Hypericum extract (309.35±6.5μg/ml was higher than the antioxidant standards, BHT (IC50=81.9±2.6 μg/ml and quercetin (IC50=60.04±6.48 μg/ml. The highest scavenging of hydroxyl radicals was observed in Hypericum extract (70.3±0.8%, 125 μg/ml. In gallic acid it was (73.8±3.3%. In 200 μg/ml of Hypericum extract scavenged NO radical (85.2±2.7%. In FRAP method, the IC50 of this extract was 109.7±10.5 μg/ml. In FTC method, the inhibition of lipid peroxidation by Hypericum extract, BHT and ascorbic acid were 59.2±2.2, 66.9±0.15, 64.06±0.02 respectively. Total phenol of the plant extract was 3±0.4 mg/g.

  12. Chemopreventive and renal protective effects for docosahexaenoic acid (DHA: implications of CRP and lipid peroxides

    Directory of Open Access Journals (Sweden)

    Darweish MM

    2009-04-01

    Full Text Available Abstract Background The fish oil-derived ω-3 fatty acids, like docosahexanoic (DHA, claim a plethora of health benefits. We currently evaluated the antitumor effects of DHA, alone or in combination with cisplatin (CP in the EAC solid tumor mice model, and monitored concomitant changes in serum levels of C-reactive protein (CRP, lipid peroxidation (measured as malondialdehyde; MDA and leukocytic count (LC. Further, we verified the capacity of DHA to ameliorate the lethal, CP-induced nephrotoxicity in rats and the molecular mechanisms involved therein. Results EAC-bearing mice exhibited markedly elevated LC (2-fold, CRP (11-fold and MDA levels (2.7-fold. DHA (125, 250 mg/kg elicited significant, dose-dependent reductions in tumor size (38%, 79%; respectively, as well as in LC, CRP and MDA levels. These effects for CP were appreciably lower than those of DHA (250 mg/kg. Interestingly, DHA (125 mg/kg markedly enhanced the chemopreventive effects of CP and boosted its ability to reduce serum CRP and MDA levels. Correlation studies revealed a high degree of positive association between tumor growth and each of CRP (r = 0.85 and leukocytosis (r = 0.89, thus attesting to a diagnostic/prognostic role for CRP. On the other hand, a single CP dose (10 mg/kg induced nephrotoxicity in rats that was evidenced by proteinuria, deterioration of glomerular filtration rate (GFR, -4-fold, a rise in serum creatinine/urea levels (2–5-fold after 4 days, and globally-induced animal fatalities after 7 days. Kidney-homogenates from CP-treated rats displayed significantly elevated MDA- and TNF-α-, but reduced GSH-, levels. Rats treated with DHA (250 mg/kg, but not 125 mg/kg survived the lethal effects of CP, and showed a significant recovery of GFR; while their homogenates had markedly-reduced MDA- and TNF-α-, but -increased GSH-levels. Significant association was detected between creatinine level and those of MDA (r = 0.81, TNF-α r = 0.92 and GSH (r = -0

  13. Generalized Anxiety Disorder (GAD) and Comorbid Major Depression with GAD Are Characterized by Enhanced Nitro-oxidative Stress, Increased Lipid Peroxidation, and Lowered Lipid-Associated Antioxidant Defenses.

    Science.gov (United States)

    Maes, Michael; Bonifacio, Kamila Landucci; Morelli, Nayara Rampazzo; Vargas, Heber Odebrecht; Moreira, Estefânia Gastaldello; St Stoyanov, Drozdstoy; Barbosa, Décio Sabbatini; Carvalho, André F; Nunes, Sandra Odebrecht Vargas

    2018-05-07

    Accumulating evidence shows that nitro-oxidative pathways play an important role in the pathophysiology of major depressive disorder (MDD) and bipolar disorder (BD) and maybe anxiety disorders. The current study aims to examine superoxide dismutase (SOD1), catalase, lipid hydroperoxides (LOOH), nitric oxide metabolites (NOx), advanced oxidation protein products (AOPP), malondialdehyde (MDA), glutathione (GSH), paraoxonase 1 (PON1), high-density lipoprotein cholesterol (HDL), and uric acid (UA) in participants with and without generalized anxiety disorder (GAD) co-occurring or not with BD, MDD, or tobacco use disorder. Z unit-weighted composite scores were computed as indices of nitro-oxidative stress driving lipid and protein oxidation. SOD1, LOOH, NOx, and uric acid were significantly higher and HDL and PON1 significantly lower in participants with GAD than in those without GAD. GAD was more adequately predicted by increased SOD + LOOH + NOx and lowered HDL + PON1 composite scores. Composite scores of nitro-oxidative stress coupled with aldehyde and AOPP production were significantly increased in participants with comorbid GAD + MDD as compared with all other study groups, namely MDD, GAD + BD, BD, GAD, and healthy controls. In conclusion, GAD is characterized by increased nitro-oxidative stress and lipid peroxidation and lowered lipid-associated antioxidant defenses, while increased uric acid levels in GAD may protect against aldehyde production and protein oxidation. This study suggests that increased nitro-oxidative stress and especially increased SOD1 activity, NO production, and lipid peroxidation as well as lowered HDL-cholesterol and PON1 activity could be novel drug targets for GAD especially when comorbid with MDD.

  14. Dermal quercetin lipid nanocapsules: Influence of the formulation on antioxidant activity and cellular protection against hydrogen peroxide.

    Science.gov (United States)

    Hatahet, T; Morille, M; Shamseddin, A; Aubert-Pouëssel, A; Devoisselle, J M; Bégu, S

    2017-02-25

    Quercetin is a plant flavonoid with strong antioxidant and antiinflammatory properties interesting for skin protection. However, its poor water solubility limits its penetration and so its efficiency on skin. For this purpose, quercetin lipid nanocapsules were formulated implementing phase inversion technique wherein several modifications were introduced to enhance quercetin loading. Quercetin lipid nanocapsules were formulated with two particle size range, (50nm and 20nm) allowing a drug loading of 18.6 and 32mM respectively. The successful encapsulation of quercetin within lipid nanocapsules increased its apparent water solubility by more than 5000 fold (from 0.5μg/ml to about 5mg/ml). The physicochemical properties of these formulations such as surface charge, stability and morphology were characterized. Lipid nanocapsules had spherical shape and were stable for 28days at 25°C. Quercetin release from lipid nanocapsules was studied and revealed a prolonged release kinetics during 24h. Using DPPH assay, we demonstrated that the formulation process of lipid nanocapsules did not modify the antioxidant activity of quercetin in vitro (92.3%). With the goal of a future dermal application, quercetin lipid nanocapsules were applied to THP-1 monocytes and proved the cellular safety of the formulation up to 2μg/ml of quercetin. Finally, formulated quercetin was as efficient as the crude form in the protection of THP-1 cells from oxidative stress by exogenous hydrogen peroxide. With its lipophilic nature and occlusive effect on skin, lipid nanocapsules present a promising strategy to deliver quercetin to skin tissue and can be of value for other poorly water soluble drug candidates. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Alterations in lipids & lipid peroxidation in rats fed with flavonoid rich fraction of banana (Musa paradisiaca) from high background radiation area.

    Science.gov (United States)

    Krishnan, Kripa; Vijayalakshmi, N R

    2005-12-01

    A group of villages in Kollam district of Kerala, southern part of India are exposed to a higher dose of natural radiation than global average. Yet no adverse health effects have been found in humans, animals and plants in these areas. The present study was carried out to understand whether radiation affects the quantity and quality of flavonoids in plants grown in this area of high radiation, and to assess the effect of feeding flavonoid rich fraction (FRF) of the two varieties of banana to rats on their biochemical parameters like lipids, lipid peroxides and antioxidant enzyme levels. A total of 42 albino rats were equally divided into 7 groups. Rats fed laboratory diet alone were grouped under group I (normal control). Groups II and V received flavonoid rich fraction (FRF) from the fruits of two varieties of Musa paradisiaca, Palayamkodan and Rasakadali respectively from normal background radiation area (Veli) and treated as controls. Rats of groups III and IV received FRF of Palayamkodan from high background radiation areas (HBRAs) - Neendakara and Karunagappally respectively while groups VI and VII received FRF of Rasakadali from HBRAs. At the end of the experimental period of 45 days, lipids, lipid peroxides and antioxidant enzymes from liver, heart and kidney were analyzed. FRF of Palayamkodan and Rasakadali varieties showed significant hypolipidaemic and antioxidant activities. But these activities were found to be lowered in plants grown in HBRAs, particularly in Karunagappally area. Of the two, Palayamkodan variety was more effective in reducing lipids and lipid peroxides. MDA and hydroperoxides were significantly diminished in rats given FRF of banana from Veli (control area) only. FRF from plants grown in HBRAs exerted inhibition in the activities of antioxidant enzymes in the liver of rats and this inhibitory effect was maximum in rats fed FRF from Karunagappally. Banana grown in HBRAs is of lower quality with less efficient antioxidant system

  16. Age-dependent variation in membrane lipid synthesis in leaves of garden pea (Pisum sativum L.)

    DEFF Research Database (Denmark)

    Hellgren, Lars; Sandelius, A.S.

    2001-01-01

    To study membrane lipid synthesis during the lifespan of a dicotyledon leaf, the second oldest leaf of 10-40-d-old plants of garden pea (Pisum sativum L.) was labelled with [1-C- 14]acetate and the distribution of radioactivity between the major membrane lipids was followed for 3 d. In the expand......To study membrane lipid synthesis during the lifespan of a dicotyledon leaf, the second oldest leaf of 10-40-d-old plants of garden pea (Pisum sativum L.) was labelled with [1-C- 14]acetate and the distribution of radioactivity between the major membrane lipids was followed for 3 d...

  17. Interaction of red pepper (Capsicum annum, Tepin) polyphenols with Fe(II)-induced lipid peroxidation in brain and liver

    Energy Technology Data Exchange (ETDEWEB)

    Oboh, G [Biochemistry Department, Federal University of Technology, Akure, Ondo State (Nigeria); [Departamento de Quimica, Universidade Federal de Santa Maria (UFSM), Campus Universitario - Camobi, Santa Maria RS (Brazil); [Abdus Salam International Centre for Theoretical Physics, Trieste (Italy)]. E-mail: goboh2001@yahoo.com; Rocha, J B.T. [Campus Universitario - Camobi, Santa Maria RS (Brazil)

    2006-03-15

    Polyphenols exhibit a wide range of biological effects because of their antioxidant properties. Several types of polyphenols (phenolic acids, hydrolyzable tannins, and flavonoids) show anticarcinogenic and antimutagenic effects. Comparative studies were carried on the protective ability of free and bound polyphenol extracts of red Capsicum annuum Tepin (CAT) on brain and liver - In vitro. Free polyphenols of red Capsicum annuum Tepin (CAT) were extracted with 80% acetone, while the bound polyphenols were extracted with ethyl acetate from acid and alkaline hydrolysis of the pepper residue from free polyphenols extract. The phenol content, Fe (II) chelating ability, OH radical scavenging ability and protective ability of the extract against Fe (II)-induced lipid peroxidation in brain and liver was subsequently determined. The results of the study revealed that the free polyphenols (218.2mg/100g) content of the pepper were significantly higher than the bound polyphenols (42.5mg/100g). Furthermore, the free polyphenol extract had a significantly higher (<0.05) Fe (II) chelating ability, OH radical scavenging ability than the bound polyphenols. In addition, both extracts significantly inhibited (P<0.05) basal and 25{mu}M Fe (II)- induced lipid peroxidation in Rat's brain and liver in a dose dependent. However, the free polyphenols caused a significantly higher inhibition in the MDA (Malondialdehyde) production in the brain and liver homogenates than the bound phenols. Furthermore, the polyphenols protected the liver more than the brain. In conclusion, free polyphenols from Capsicum annuum protects both the liver and brain from Fe{sup 2+} induced lipid peroxidation, and this is probably due to the higher Fe (II) chelating ability and OH radical scavenging ability of the free polyphenols from the pepper. (author)

  18. Influence of electromagnetic field (1800 MHz on lipid peroxidation in brain, blood, liver and kidney in rats

    Directory of Open Access Journals (Sweden)

    Paweł Bodera

    2015-08-01

    Full Text Available Objectives: The aim of this study is the evaluation of the influence of repeated (5 times for 15 min exposure to electromagnetic field (EMF of 1800 MHz frequency on tissue lipid peroxidation (LPO both in normal and inflammatory state, combined with analgesic treatment. Material and Methods: The concentration of malondialdehyde (MDA as the end-product of the lipid peroxidation (LPO was estimated in blood, liver, kidneys, and brain of Wistar rats, both healthy and those with complete Freund’s adjuvant (CFA-induced persistent paw inflammation. Results: The slightly elevated levels of the MDA in blood, kidney, and brain were observed among healthy rats in electromagnetic field (EMF-exposed groups, treated with tramadol (TRAM/EMF and exposed to the EMF. The malondialdehyde remained at the same level in the liver in all investigated groups: the control group (CON, the exposed group (EMF, treated with tramadol (TRAM as well as exposed to and treated with tramadol (TRAM/EMF. In the group of animals treated with the complete Freund’s adjuvant (CFA we also observed slightly increased values of the MDA in the case of the control group (CON and the exposed groups (EMF and TRAM/EMF. The MDA values concerning kidneys remained at the same levels in the control, exposed, and not-exposed group treated with tramadol. Results for healthy rats and animals with inflammation did not differ significantly. Conclusions: The electromagnetic field exposure (EMF, applied in the repeated manner together with opioid drug tramadol (TRAM, slightly enhanced lipid peroxidation level in brain, blood, and kidneys.

  19. ROLE OF PHYSICAL EXERCISE, FITNESS AND AEROBIC TRAINING IN TYPE 1 DIABETIC AND HEALTHY MEN IN RELATION TO THE LIPID PROFILE, LIPID PEROXIDATION AND THE METABOLIC SYNDROME

    Directory of Open Access Journals (Sweden)

    David E. Laaksonen

    2003-06-01

    Full Text Available Dyslipidemia and possibly lipid peroxidation play important roles in the development of macro- and microvascular disease in type 1 diabetes mellitus. Little is known, however, of the role of aerobic exercise in dyslipidemia and resting and exercise-induced lipid peroxidation in type 1 diabetes. Despite the well-known effect of leisure-time physical activity (LTPA on components of the metabolic syndrome, little is known of the association of LTPA and cardiorespiratory fitness (maximal oxygen consumption, VO2max with development of the metabolic syndrome itself. A randomized controlled trial assessing the effect of a 12-16 week aerobic exercise program on VO2max and the lipid profile was carried out in otherwise healthy young men with type 1 diabetes. The effect of acute physical exercise on oxidative stress and antioxidant defenses and the relation to VO2max in men with type 1 diabetes was also evaluated. To test four recently proposed definitions by the World Health Organization (WHO and National Cholesterol Education Program (NCEP of the metabolic syndrome, the sensitivity and specificity of the definitions for prevalent and incident diabetes were assessed in a population-based cohort of middle-aged men. We also studied the associations of LTPA and cardiorespiratory fitness with prevalent and incident cases of the metabolic syndrome. A 12-16 week endurance exercise program produced antiatherogenic changes in lipid, lipoprotein and apolipoprotein levels in 20 type 1 diabetic men who for the most part were already physically active at baseline. The most favorable training-induced changes in the high-density lipoprotein cholesterol (HDL/low-density lipoprotein cholesterol (LDL and apolipoprotein A-I/apolipoprotein B ratios were in patients with low baseline HDL/LDL levels, likely the group with the most benefit to be gained by such changes. Plasma thiobarbituric acid reactive substances (TBARS, a measure of lipid peroxidation, was higher in nine

  20. Water extractable phytochemicals from Capsicum pubescens (tree pepper) inhibit lipid peroxidation induced by different pro-oxidant agents in brain

    Energy Technology Data Exchange (ETDEWEB)

    Oboh, G [Biochemistry Department, Federal University of Technology, Akure, Ondo State (Nigeria); [Departamento de Quimica, Universidade Federal de Santa Maria (UFSM), Campus Universitario - Camobi, Santa Maria RS (Brazil); [Abdus Salam International Centre for Theoretical Physics, Trieste (Italy)]. E-mail: goboh2001@yahoo.com; Rocha, J B.T. [Campus Universitario - Camobi, Santa Maria RS (Brazil)

    2006-03-15

    Reactive oxygen species (ROS) is the cause of neurodegenerative disorders such as Lou Gehrig's disease, Parkinson's disease and Huntington's disease; one practical way to prevent and manage neurodegenerative diseases is through the eating of food rich in antioxidants (dietary means). In this study, the antioxidant and neuroprotective properties of aqueous extract of ripe and unripe Capsicum pubescens (popularly known as tree pepper) on different pro-oxidant induced lipid peroxidation in Rat's brain (in vitro) is been investigated. Aqueous extract of freshly harvested pepper was prepared, and the total phenol content, vitamin C, ferric reducing antioxidant property (FRAP) and Fe (II) chelating ability was determined. In addition, the ability of the extracts to protect the Rat's brain against some pro-oxidant FeSO{sub 4}, Sodium nitroprusside and Quinolinic acid - induced oxidative stress was also determined. The results of the study revealed that ripe Capsicum pubescens had a significantly higher (P<0.05) total phenol [ripe (113.7mg/100g), unripe (70.5mg/100g)] content and ferric reducing antioxidant property than the unripe pepper. However, there was no significant difference in the vitamin C [ripe (231.5{mu}g/g), unripe (224.4{mu}g/g)] content and Fe (II) chelating ability. Furthermore, the pepper extracts caused a significant decrease (P<0.05) in 25{mu}M Fe(II), 7{mu}M Sodium Nitroprusside and 1mM Quinolinic acid induced lipid peroxidation in the Rat's brain in a dose-dependent manner. However, the ripe pepper inhibited MDA (Malondialdehyhide) production in the Rat's brain than the unripe pepper. Conversely, both extract did not significantly inhibit Fe (II)/H{sub 2}O{sub 2} induced decomposition of deoxyribose. Therefore, ripe and unripe Capsicum pubescens would inhibit lipid peroxidation in vitro. However, the ripe potent was a more potent inhibitor of lipid peroxidation, which is probably due to its higher vitamin C and phenol content, reducing power and Fe

  1. Effect of repeated oral administration of bifenthrin on lipid peroxidation and anti-oxidant parameters in Wistar rats.

    Science.gov (United States)

    Dar, Muneer Ahmad; Khan, Adil Mehraj; Raina, Rajinder; Verma, Pawan Kumar; Sultana, Mudasir

    2013-07-01

    The oxidative stress-inducing potential of the pyrethroid insecticide, bifenthrin, was evaluated in rats at 5.8 mg/kg body weight once daily for 20 or 30 days. Bifenthrin treated animals showed significantly increased lipid peroxidation, evidenced by increased blood malondialdehyde levels. Blood glutathione levels and activities of catalase and glutathione peroxidase decreased significantly in the bifenthrin treated animals after both 20 and 30 days of treatment, whereas, the activities of superoxide dismutase and glutathione S-transferase decreased significantly only on the 30th day. In conclusion, bifenthrin has a potential to induce severe oxidative stress in rats exposed to sublethal concentrations.

  2. Effect of gamma irradiation on the lipid peroxidation in chicken, lamb and buffalo meat during chilled storage

    International Nuclear Information System (INIS)

    Kanatt, S.R.; Paul, P.; D'Souza, S.F.; Thomas, P.

    1997-01-01

    Chicken, lamb and buffalo meat were subjected to low-dose gamma irradiation (2.5 kGy) and stored at 0-3C. Lipid peroxidation in terms of thiobarbituric acid (TBA) number and carbonyl content were monitored during storage. While irradiated meat showed slight increase in TBA number and carbonyl content on storage as compared to nonirradiated meat, this did not affect the sensory qualities of meat. Free fatty acid content decreased markedly on irradiation. Irradiated meats were microbiologically safe and sensorily acceptable up to 4 weeks in the nonfrozen state (0-3C) while nonirradiated meat had a shelf-life of less than 2 weeks

  3. [Cholesterol metabolism and lipid peroxidation processes in hypodynamia. Effect of using ascorbic acid and alpha-tocopherol].

    Science.gov (United States)

    Elikov, A V; Tsapok, P I

    2010-01-01

    Study status of cholesterol metabolism, processes of lipid peroxidation and antioxidant protection in blood plasma, erythrocytes and homogenates of the, heart, liver, muscle femors of rats attached to movement active. Establishment effects application of ascorbic acid and alpha-tocopherol. Ascorbic acid and alpha-tocopherol were infused daily. The daily dosage was 2 and 1 mg respectively. Characteristic shift changes of cholesterol metabolism in conditions of limited muscular activity were revealed. It was shown that vitamin antioxidants play a role in correction of metabolic disorders in case of immobile distress syndrome.

  4. How synthetic membrane systems contribute to the understanding of lipid-driven endocytosis.

    Science.gov (United States)

    Schubert, Thomas; Römer, Winfried

    2015-11-01

    Synthetic membrane systems, such as giant unilamellar vesicles and solid supported lipid bilayers, have widened our understanding of biological processes occurring at or through membranes. Artificial systems are particularly suited to study the inherent properties of membranes with regard to their components and characteristics. This review critically reflects the emerging molecular mechanism of lipid-driven endocytosis and the impact of model membrane systems in elucidating the complex interplay of biomolecules within this process. Lipid receptor clustering induced by binding of several toxins, viruses and bacteria to the plasma membrane leads to local membrane bending and formation of tubular membrane invaginations. Here, lipid shape, and protein structure and valency are the essential parameters in membrane deformation. Combining observations of complex cellular processes and their reconstitution on minimal systems seems to be a promising future approach to resolve basic underlying mechanisms. This article is part of a Special Issue entitled: Mechanobiology. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. On the Mechanism of Cytoprotection by Ferrostatin-1 and Liproxstatin-1 and the Role of Lipid Peroxidation in Ferroptotic Cell Death

    OpenAIRE

    Zilka, Omkar; Shah, Ron; Li, Bo; Friedmann Angeli, Jos? Pedro; Griesser, Markus; Conrad, Marcus; Pratt, Derek A.

    2017-01-01

    Ferroptosis is a form of regulated necrosis associated with the iron-dependent accumulation of lipid hydroperoxides that may play a key role in the pathogenesis of degenerative diseases in which lipid peroxidation has been implicated. High-throughput screening efforts have identified ferrostatin-1 (Fer-1) and liproxstatin-1 (Lip-1) as potent inhibitors of ferroptosis ? an activity that has been ascribed to their ability to slow the accumulation of lipid hydroperoxides. Herein we demonstrate t...

  6. Changes in glutathione system and lipid peroxidation in rat blood during the first hour after chlorpyrifos exposure

    Directory of Open Access Journals (Sweden)

    V. P. Rosalovsky

    2015-10-01

    Full Text Available Chlorpyrifos (CPF is a highly toxic organophosphate compound, widely used as an active substance of many insecticides. Along with the anticholinesterase action, CPF may affect other biochemical mechanisms, particularly through disrupting pro- and antioxidant balance and inducing free-radical oxidative stress. Origins and occurrence of these phenomena are still not fully understood. The aim of our work was to investigate the effects of chlorpyrifos on key parameters of glutathione system and on lipid peroxidation in rat blood in the time dynamics during one hour after exposure. We found that a single exposure to 50 mg/kg chlorpyrifos caused a linear decrease in butyryl cholinesterase activity, increased activity of glutathione peroxidase and glutathione reductase, alterations in the levels of glutathione, TBA-active products and lipid hydroperoxides during 1 hour after poisoning. The most significant changes in studied parameters were detected at the 15-30th minutes after chlorpyrifos exposure.

  7. Comparative investigation on the effect of T-2 mycotoxin on lipid peroxidation and antioxidant status in different poultry species.

    Science.gov (United States)

    Mézes, M; Barta, M; Nagy, G

    1999-02-01

    The effect of low dose T-2 toxin was investigated in chicken, duck and goose. The purpose of the present study was to investigate the effect of T-2 toxin on the lipid peroxidation and on the activity of glutathione redox system (amount of reduced and oxidised glutathione and the activity of glutathione peroxidase) in blood and liver. The treatment lasted days and two samples were taken, first at the time of lowest feed intake and second when the intake was the same as the control. It was found, that lipid per oxidation as detected by the amount of malondialdehyde increased in all of the species and tissues but the changes varied by species. The most sensitive species was goose followed by duck and chicken, and the most sensitive tissue was the liver followed by blood plasma and red blood cells.

  8. Rotavirus RRV associates with lipid membrane microdomains during cell entry

    International Nuclear Information System (INIS)

    Isa, Pavel; Realpe, Mauricio; Romero, Pedro; Lopez, Susana; Arias, Carlos F.

    2004-01-01

    Rotavirus cell entry is a multistep process, not completely understood, which requires at least four interactions between the virus and cell surface molecules. In this work, we investigated the role of the sphingolipid- and cholesterol-enriched lipid microdomains (rafts) in the entry of rotavirus strain RRV to MA104 cells. We found that ganglioside GM1, integrin subunits α2 and β3, and the heat shock cognate protein 70 (hsc70), all of which have been implicated as rotavirus receptors, are associated with TX-100 and Lubrol WX detergent-resistant membranes (DRMs). Integrin subunits α2 and β3 were found to be particularly enriched in DRMs resistant to lysis by Lubrol WX. When purified RRV particles were incubated with cells at 4 deg. C, about 10% of the total infectious virus was found associated with DRMs, and the DRM-associated virus increased to 37% in Lubrol-resistant membrane domains after 60-min incubation at 37 deg. C. The virus was excluded from DRMs if the cells were treated with methyl-β-cyclodextrin (MβCD). Immunoblot analysis of the viral proteins showed that the virus surface proteins became enriched in DRMs upon incubation at 37 deg. C, being almost exclusively localized in Lubrol-resistant DRMs after 60 min. These data suggest that detergent-resistant membrane domains play an important role in the cell entry of rotaviruses, which could provide a platform to facilitate the efficient interaction of the rotavirus receptors with the virus particle

  9. Efficient replacement of plasma membrane outer leaflet phospholipids and sphingolipids in cells with exogenous lipids.

    Science.gov (United States)

    Li, Guangtao; Kim, JiHyun; Huang, Zhen; St Clair, Johnna R; Brown, Deborah A; London, Erwin

    2016-12-06

    Our understanding of membranes and membrane lipid function has lagged far behind that of nucleic acids and proteins, largely because it is difficult to manipulate cellular membrane lipid composition. To help solve this problem, we show that methyl-α-cyclodextrin (MαCD)-catalyzed lipid exchange can be used to maximally replace the sphingolipids and phospholipids in the outer leaflet of the plasma membrane of living mammalian cells with exogenous lipids, including unnatural lipids. In addition, lipid exchange experiments revealed that 70-80% of cell sphingomyelin resided in the plasma membrane outer leaflet; the asymmetry of metabolically active cells was similar to that previously defined for erythrocytes, as judged by outer leaflet lipid composition; and plasma membrane outer leaflet phosphatidylcholine had a significantly lower level of unsaturation than phosphatidylcholine in the remainder of the cell. The data also provided a rough estimate for the total cellular lipids residing in the plasma membrane (about half). In addition to such lipidomics applications, the exchange method should have wide potential for investigations of lipid function and modification of cellular behavior by modification of lipids.

  10. Lipid recognition propensities of amino acids in membrane proteins from atomic resolution data

    International Nuclear Information System (INIS)

    Morita, Mizuki; Katta, AVSK Mohan; Ahmad, Shandar; Mori, Takaharu; Sugita, Yuji; Mizuguchi, Kenji

    2011-01-01

    Protein-lipid interactions play essential roles in the conformational stability and biological functions of membrane proteins. However, few of the previous computational studies have taken into account the atomic details of protein-lipid interactions explicitly. To gain an insight into the molecular mechanisms of the recognition of lipid molecules by membrane proteins, we investigated amino acid propensities in membrane proteins for interacting with the head and tail groups of lipid molecules. We observed a common pattern of lipid tail-amino acid interactions in two different data sources, crystal structures and molecular dynamics simulations. These interactions are largely explained by general lipophilicity, whereas the preferences for lipid head groups vary among individual proteins. We also found that membrane and water-soluble proteins utilize essentially an identical set of amino acids for interacting with lipid head and tail groups. We showed that the lipophilicity of amino acid residues determines the amino acid preferences for lipid tail groups in both membrane and water-soluble proteins, suggesting that tightly-bound lipid molecules and lipids in the annular shell interact with membrane proteins in a similar manner. In contrast, interactions between lipid head groups and amino acids showed a more variable pattern, apparently constrained by each protein's specific molecular function

  11. Lipid recognition propensities of amino acids in membrane proteins from atomic resolution data

    Directory of Open Access Journals (Sweden)

    Morita Mizuki

    2011-12-01

    Full Text Available Abstract Background Protein-lipid interactions play essential roles in the conformational stability and biological functions of membrane proteins. However, few of the previous computational studies have taken into account the atomic details of protein-lipid interactions explicitly. Results To gain an insight into the molecular mechanisms of the recognition of lipid molecules by membrane proteins, we investigated amino acid propensities in membrane proteins for interacting with the head and tail groups of lipid molecules. We observed a common pattern of lipid tail-amino acid interactions in two different data sources, crystal structures and molecular dynamics simulations. These interactions are largely explained by general lipophilicity, whereas the preferences for lipid head groups vary among individual proteins. We also found that membrane and water-soluble proteins utilize essentially an identical set of amino acids for interacting with lipid head and tail groups. Conclusions We showed that the lipophilicity of amino acid residues determines the amino acid preferences for lipid tail groups in both membrane and water-soluble proteins, suggesting that tightly-bound lipid molecules and lipids in the annular shell interact with membrane proteins in a similar manner. In contrast, interactions between lipid head groups and amino acids showed a more variable pattern, apparently constrained by each protein's specific molecular function.

  12. Hydrostatic pressure decreases membrane fluidity and lipid desaturase expression in chondrocyte progenitor cells.

    Science.gov (United States)

    Montagne, Kevin; Uchiyama, Hiroki; Furukawa, Katsuko S; Ushida, Takashi

    2014-01-22

    Membrane biomechanical properties are critical in modulating nutrient and metabolite exchange as well as signal transduction. Biological membranes are predominantly composed of lipids, cholesterol and proteins, and their fluidity is tightly regulated by cholesterol and lipid desaturases. To determine whether such membrane fluidity regulation occurred in mammalian cells under pressure, we investigated the effects of pressure on membrane lipid order of mouse chondrogenic ATDC5 cells and desaturase gene expression. Hydrostatic pressure linearly increased membrane lipid packing and simultaneously repressed lipid desaturase gene expression. We also showed that cholesterol mimicked and cholesterol depletion reversed those effects, suggesting that desaturase gene expression was controlled by the membrane physical state itself. This study demonstrates a new effect of hydrostatic pressure on mammalian cells and may help to identify the molecular mechanisms involved in hydrostatic pressure sensing in chondrocytes. © 2013 Elsevier Ltd. All rights reserved.

  13. Shiga toxin induces membrane reorganization and formation of long range lipid order

    DEFF Research Database (Denmark)

    Solovyeva, Vita; Johannes, Ludger; Simonsen, Adam Cohen

    2015-01-01

    membrane reordering. When Shiga toxin was added above the lipid chain melting temperature, the toxin interaction with the membrane induced rearrangement and clustering of Gb3 lipids that resulted in the long range order and alignment of lipids in gel domains. The toxin induced redistribution of Gb3 lipids...... inside gel domains is governed by the temperature at which Shiga toxin was added to the membrane: above or below the phase transition. The temperature is thus one of the critical factors controlling lipid organization and texture in the presence of Shiga toxin. Lipid chain ordering imposed by Shiga toxin...... binding can be another factor driving the reconstruction of lipid organization and crystallization of lipids inside gel domains....

  14. The membrane stress response buffers lethal effects of lipid disequilibrium by reprogramming the protein homeostasis network.

    Science.gov (United States)

    Thibault, Guillaume; Shui, Guanghou; Kim, Woong; McAlister, Graeme C; Ismail, Nurzian; Gygi, Steven P; Wenk, Markus R; Ng, Davis T W

    2012-10-12

    Lipid composition can differ widely among organelles and even between leaflets of a membrane. Lipid homeostasis is critical because disequilibrium can have disease outcomes. Despite their importance, mechanisms maintaining lipid homeostasis remain poorly understood. Here, we establish a model system to study the global effects of lipid imbalance. Quantitative lipid profiling was integral to monitor changes to lipid composition and for system validation. Applying global transcriptional and proteomic analyses, a dramatically altered biochemical landscape was revealed from adaptive cells. The resulting composite regulation we term the "membrane stress response" (MSR) confers compensation, not through restoration of lipid composition, but by remodeling the protein homeostasis network. To validate its physiological significance, we analyzed the unfolded protein response (UPR), one facet of the MSR and a key regulator of protein homeostasis. We demonstrate that the UPR maintains protein biogenesis, quality control, and membrane integrity-functions otherwise lethally compromised in lipid dysregulated cells. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Synergistic Effects of Squalene and Omega-3 on Lipid Peroxidation and some Antioxidants in Gamma-Irradiated Male Albino Rats

    International Nuclear Information System (INIS)

    Ahmed, A. G.; Abdel-Magied, N.

    2011-01-01

    The present study aims to investigate the synergistic effects of squalene and omega-3 as an antioxidant in protection against oxidative stress which induced by gamma- irradiated in male albino rats. The experimental animals, male albino rats (n=48) weighing (120-150 g) were divided into 4 groups: control, gamma irradiated with a single dose of 6 Gy, oral administration with 0.4 ml/kg b. wt from squalene and omega-3 for 30 days and oral administration with 0.4 ml/kg b. wt from squalene and omega-3 for 30 days and irradiated with a single dose level (6 Gy). Animals were sacrificed on the 3rd and 7th day post irradiation. Biochemical analysis was carried out on blood glutathione content (GSH), superoxide dismutase activity (SOD), catalase activity (CAT) and lipid peroxidation (MDA). Also lipid profile: plasma total cholesterol (TC), triglycerides (TG), LDL-cholesterol (LDL-C) and HDL-cholesterol (HDL-C) were assayed. Exposure to gamma radiation at dose level 6 Gy elevated significantly lipid peroxidation (MDA) and decline in level of blood glutathione content (GSH), superoxide dismutase activity (SOD), and catalase activity (CAT) also, a significant increase in plasma total cholesterol (TC), triglycerides (TG), LDL-cholesterol (LDL-C) and decrease in HDL-cholesterol (HDL-C). Combined supplementation of squalene and omega-3 significantly prevented the elevation of (MDA) and decline in antioxidant parameters after radiation and ameliorates plasma lipid profile. The results indicated that the combination of aqualene and omega-3 has a protective role, antioxidant effect and antilipidemic effect against gamma radiation in exposed rats

  16. Peroxides and radiation impairment of oxidative phosphorylation

    Energy Technology Data Exchange (ETDEWEB)

    Dovgii, I E; Akoev, I G

    1975-09-01

    An increase in the peroxidase activity of the mitochondria and a simultaneous rise in the amount of peroxide compounds, which are half lipid-like substances, are detected within the first 10 minutes after irradiation (1000 r). A mechanism of radiation impairment of oxidative phosphorylation is connected with the penetration of its inhibitors to the mitochondria due to the disturbed permeability of membranes affected by peroxides.

  17. Reconstitution of a Kv channel into lipid membranes for structural and functional studies.

    Science.gov (United States)

    Lee, Sungsoo; Zheng, Hui; Shi, Liang; Jiang, Qiu-Xing

    2013-07-13

    To study the lipid-protein interaction in a reductionistic fashion, it is necessary to incorporate the membrane proteins into membranes of well-defined lipid composition. We are studying the lipid-dependent gating effects in a prototype voltage-gated potassium (Kv) channel, and have worked out detailed procedures to reconstitute the channels into different membrane systems. Our reconstitution procedures take consideration of both detergent-induced fusion of vesicles and the fusion of protein/detergent micelles with the lipid/detergent mixed micelles as well as the importance of reaching an equilibrium distribution of lipids among the protein/detergent/lipid and the detergent/lipid mixed micelles. Our data suggested that the insertion of the channels in the lipid vesicles is relatively random in orientations, and the reconstitution efficiency is so high that no detectable protein aggregates were seen in fractionation experiments. We have utilized the reconstituted channels to determine the conformational states of the channels in different lipids, record electrical activities of a small number of channels incorporated in planar lipid bilayers, screen for conformation-specific ligands from a phage-displayed peptide library, and support the growth of 2D crystals of the channels in membranes. The reconstitution procedures described here may be adapted for studying other membrane proteins in lipid bilayers, especially for the investigation of the lipid effects on the eukaryotic voltage-gated ion channels.

  18. The Effects of Subacute Exposure of Peracetic Acid on Lipid Peroxidation and Hepatic Enzymes in Wistar Rats

    Directory of Open Access Journals (Sweden)

    Abdoljalal Marjani

    2010-10-01

    Full Text Available Objectives: This study was undertaken to determine the effect of subacute exposure of peracetic acid on lipid peroxidation and hepatic enzymes in Wistar rats.Methods: 48 male animals in Treatment Group I, II and III received 0.2%, 2% and 20% peracetic acid daily for 2 and 4 weeks.Results: Serum malondialdehyde increased and Alanine Transaminase and Aspartate Transaminase decreased significantly in groups 2 and 3, compared to the control group. The malondialdehyde, Alanine Transaminase and Aspartate Transaminase with 0.2% and 2% doses of peracetic acid for 2 weeks do not lead to the alteration of malondialdehyde and enzyme activities.Conclusion: This study demonstrated that the enhancement of malondialdehyde could provide an oxidative damage induced by disinfectant peroxidation at 20% and 2% doses at 2 and 4 weeks. The consumption of peroxidation with 20% for 2 weeks and 2% for 4 weeks can cause the increase of malondialdehyde and the decrease of enzyme activities, respectively.

  19. Inhibition of Oxidative Stress and Lipid Peroxidation by Anthocyanins from Defatted Canarium odontophyllum Pericarp and Peel Using In Vitro Bioassays

    Science.gov (United States)

    Khoo, Hock Eng; Azlan, Azrina; Ismail, Amin; Abas, Faridah; Hamid, Muhajir

    2014-01-01

    Canarium odontophyllum, also known as CO, is a highly nutritious fruit. Defatted parts of CO fruit are potent sources of nutraceutical. This study aimed to determine oxidative stress and lipid peroxidation effects of defatted CO pericarp and peel extracts using in vitro bioassays. Cell cytotoxic effect of the CO pericarp and peel extracts were also evaluated using HUVEC and Chang liver cell lines. The crude extracts of defatted CO peel and pericarp showed cytoprotective effects in t-BHP and 40% methanol-induced cell death. The crude extracts also showed no toxic effect to Chang liver cell line. Using CD36 ELISA, NAD+ and LDL inhibition assays, inhibition of oxidative stress were found higher in the crude extract of defatted CO peel compared to the pericarp extract. Hemoglobin and LDL oxidation assays revealed both crude extracts had significantly reduced lipid peroxidation as compared to control. TBARS values among defatted CO pericarp, peel, and cyanidin-3-glucoside showed no significant differences for hemoglobin and LDL oxidation assays. The protective effects of defatted CO parts, especially its peel is related to the presence of high anthocyanin that potentially offers as a pharmaceutical ingredient for cardioprotection. PMID:24416130

  20. Effect of the Gamma Radiation and Temperature on Histamine Production, Lipid Peroxidation and Antioxidant Parameters in Sardine (Sardina Pilchardus)

    International Nuclear Information System (INIS)

    Maltar-Strmecki, N.; Aladrovic, J.; Dzaja, P.; Ljubic-Beer, B.; Laskaj, R.

    2013-01-01

    Radiation processing of fish is recognized as a safe and effective method for reducing microorganisms and viruses as well for inactivating pathogens among the existing technologies for preservation. Safety and hygienic quality is directly related to the duration between when the fish is caught and when it reaches the end consumer and depends upon conditions how the sardine is handled and upon which conditions. As sardine (Sardina pilchardus Walbaum, 1792) is pelagric fish widely distributed in the Adriatic Sea and one of the most commercially important fish species in the fisheries of all countries located along the coast of the Adriatic Sea in the present study, the effects of gamma irradiation on the histamine production, lipid peroxidation and antioxidant parameters in sardine during the storage at two different temperatures (4 and 30 degrees of Celsius) were investigated. The results indicate that histamine concentration was reduced by gamma irradiation and that the safe consumption can be prolonged for both temperatures of storage. However, irradiation treatment induced oxidative damage, as evidenced by changes in levels of lipid peroxidation and radical kinetic rate detected by EPR (electron paramagnetic resonance) spectroscopy. These results suggest that gamma radiation undoubtedly induces antioxidant defence system in sardine fish. However, further research is necessary to elucidate the precise role that the antioxidant system plays under the influence of gamma radiation and temperature.(author)

  1. Interaction of red pepper (Capsicum annum, Tepin) polyphenols with Fe(II)-induced lipid peroxidation in brain and liver

    International Nuclear Information System (INIS)

    Oboh, G.; Rocha, J.B.T.

    2006-03-01

    Polyphenols exhibit a wide range of biological effects because of their antioxidant properties. Several types of polyphenols (phenolic acids, hydrolyzable tannins, and flavonoids) show anticarcinogenic and antimutagenic effects. Comparative studies were carried on the protective ability of free and bound polyphenol extracts of red Capsicum annuum Tepin (CAT) on brain and liver - In vitro. Free polyphenols of red Capsicum annuum Tepin (CAT) were extracted with 80% acetone, while the bound polyphenols were extracted with ethyl acetate from acid and alkaline hydrolysis of the pepper residue from free polyphenols extract. The phenol content, Fe (II) chelating ability, OH radical scavenging ability and protective ability of the extract against Fe (II)-induced lipid peroxidation in brain and liver was subsequently determined. The results of the study revealed that the free polyphenols (218.2mg/100g) content of the pepper were significantly higher than the bound polyphenols (42.5mg/100g). Furthermore, the free polyphenol extract had a significantly higher ( 2+ induced lipid peroxidation, and this is probably due to the higher Fe (II) chelating ability and OH radical scavenging ability of the free polyphenols from the pepper. (author)

  2. Effect of Withania Somnifera Root Powder on the Levels of Circulatory Lipid Peroxidation and Liver Marker Enzymes in Chronic Hyperammonemia

    Directory of Open Access Journals (Sweden)

    B. Harikrishnan

    2008-01-01

    Full Text Available Withania somnifera (L Dunal (Solanaceae, commonly called Ashwagandha (Sanskrit is an Ayurvedic Indian medicinal plant, which has been widely used as a home remedy for several ailments. We have investigated the influence of W.somnifera root powder on the levels of circulatory ammonia, urea, lipid peroxidation products such as TBARS (thiobarbituric acid and reactive substances, HP (hydroperoxides and liver marker enzymes such as AST (aspartate transaminase, ALT (alanine transaminase and ALP (alkaline phosphatase, for its hepatoprotective effect in ammonium chloride induced hyperammonemia. Ammonium chloride treated rats showed a significant increase in the levels of circulatory ammonia, urea, AST, ALT, ALP, TBARS and HP. These changes were significantly decreased in rats treated with W.somnifera root powder and ammonium chloride. Our results indicate that W.somnifera offers hepatoprotection by influencing the levels of lipid peroxidation products and liver markers in experimental hyperammonemia and this could be due to (i the presence of alkaloids, withanolids and flavonoids, (ii normalizing the levels of urea and urea related compounds, (iii its free radical scavenging property and (iv its antioxidant property. The exact underlying mechanism is still unclear and further research needed.

  3. Relation of fatty acid composition in lead-exposed mallards to fat mobilization, lipid peroxidation and alkaline phosphatase activity

    Science.gov (United States)

    Mateo, R.; Beyer, W.N.; Spann, J.W.; Hoffman, D.J.

    2003-01-01

    The increase of n-6 polyunsaturated fatty acids (PUFA) in animal tissues has been proposed as a mechanism of lead (Pb) poisoning through lipid peroxidation or altered eicosanoids metabolism. We have studied fatty acid (FA) composition in liver and brain of mallards (Anas platyrhynchos) feeding for 3 weeks on diets containing combinations of low or high levels of vitamin E (20 or 200 UI/kg) and Pb (0 or 2 g/kg). Saturated FA, n-6 PUFA and total concentrations of FA were higher in livers of Pb-exposed mallards, but not in their brains. The percentage of n-6 PUFA in liver and brain was slightly higher in Pb-exposed mallards. The increase of n-6 PUFA in liver was associated with decreased triglycerides and increased cholesterol in plasma, thus could be in part attributed to feed refusal and fat mobilization. The hepatic ratios between adrenic acid (22:4 n-6) and arachidonic acid (20:4 n-6) or between adrenic acid and linoleic acid (18:2 n-6) were higher in Pb exposed birds, supporting the existing hypothesis of increased fatty acid elongation by Pb. Among the possible consequences of increased n-6 PUFA concentration in tissues, we found increased lipid peroxidation in liver without important histopathological changes, and decreased plasma alkaline phosphatase activity that may reflect altered bone metabolism in birds.

  4. Lipid peroxidation and decline in antioxidant status as one of the toxicity measures of diazinon in the testis.

    Science.gov (United States)

    Leong, Chong Thau; D'Souza, Urban J A; Iqbal, Mohammad; Mustapha, Zainal Arifin

    2013-01-01

    The rapid emergence of various pesticides in the market is inevitable due to the demands from agriculture industries and domestic needs to control nuisance pests and to sustain green resources worldwide. However, long-term exposure to pesticide has led to adverse effects on male fertility. Organophosphate diazinon (O,O-diethyl-O-[2-isopropyl-6-methyl-4-pyrimidinyl] phosphorothiote) is an often abusively used pesticide, as it is effective and economical. This study is to determine the adverse effects of low-dose diazinon exposure on the male reproductive system. In this study, 72 Sprague-Dawley rats were segregated into 1, 2, and 8 weeks of exposure groups and further sub-grouped (n = 6) to receive 0, 10, 15, and 30 mg/kg body weight diazinon treatment. Rats were gavaged orally with diazinon and sacrificed under anaesthesia the day after the last exposure. Our results showed that consistent diazinon exposure decreased glutathione and catalase, and increased lipid peroxidation which together lead to diazinon-mediated oxidative stress. Additionally, diazinon increased serum lactate dehydrogenase and decreased serum testosterone, which may have caused sperm and histopathological anomalies. In conclusion, exposure to diazinon caused changes in lipid peroxidation and sperm, and these two effects might be causally linked.

  5. Platelet rebound effect of alcohol withdrawal and wine drinking in rats. Relation to tannins and lipid peroxidation.

    Science.gov (United States)

    Ruf, J C; Berger, J L; Renaud, S

    1995-01-01

    We investigated in rats fed a purified diet for 2 and 4 months whether wine drinking was associated with the rebound effect on thrombin-induced platelet aggregation observed after alcohol withdrawal. With 6% ethanol drinking or its equivalent in red or white wine, platelet aggregation was reduced similarly by 70% when the animals drank the alcoholic beverages up to the venipuncture. Depriving the rats of alcoholic beverages for 18 hours was associated with an increase in the platelet response of 124% in those receiving 6% ethanol, of 46% with white wine but a decrease of 59% in those with red wine. The protective effect of red wine on platelets could be reproduced by tannins (procyanidins) extracted from grape seeds or red wine and added to 6% ethanol, but not by glycerol or wine without alcohol. That was related to inhibition of the alcohol-induced lipid peroxidation as shown by the lowering of conjugated dienes, lipid peroxides, and the increase in vitamin E in plasma. Owing to tannins, the platelets of rats drinking red wine did not exhibit the rebound effect observed hours after alcohol drinking, eventually associated with sudden death and stroke in humans.

  6. Oral and intraperitoneal administration of quercetin decreased lymphocyte DNA damage and plasma lipid peroxidation induced by TSA in vivo.

    Science.gov (United States)

    Chan, Shu-Ting; Lin, Yi-Chin; Chuang, Cheng-Hung; Shiau, Rong-Jen; Liao, Jiunn-Wang; Yeh, Shu-Lan

    2014-01-01

    Our previous study showed that quercetin enhances the anticancer effect of trichostatin A (TSA) in xenograft mice given quercetin intraperitoneally (10 mg/kg, 3 times/week). Herein, we investigate whether quercetin administered orally exerts such an effect and prevents the cytotoxic side effects of TSA. We found that quercetin given orally (20 and 100 mg/kg, 3 times/week) failed to enhance the antitumor effect of TSA although it increased the total quercetin concentration more than quercetin administered intraperitoneally in the plasma. The compound quercetin-3-glucuronide (Q3G) increased the most. However, quercetin administered intraperitoneally increased the total quercetin level in tumor tissues more than oral quercetin. Oral and intraperitoneal administration of quercetin similarly decreased lymphocyte DNA damage and plasma lipid peroxidation level induced by TSA. Furthermore, we found that the enhancing effect of Q3G on the antitumor effect of TSA and the incorporation of Q3G was less than that of quercetin in A549 cells. However, we found that A549 cells possessed the ability to convert Q3G to quercetin. In conclusion, different from quercetin administered intraperitoneally, quercetin administered orally failed to enhance the antitumor effect of TSA because of its metabolic conversion. However, it prevented TSA-induced DNA damage and lipid peroxidation.

  7. Antioxidant, lipid peroxidation inhibition and free radical scavenging efficacy of a diterpenoid compound sugiol isolated from Metasequoia glyptostroboides.

    Science.gov (United States)

    Bajpai, Vivek K; Sharma, Ajay; Kang, Sun Chul; Baek, Kwang-Hyun

    2014-01-01

    To investigate the antioxidant efficacy of a biologically active diterpenoid compound sugiol isolated from Metasequoia glyptostroboides (M. glyptostroboides) in various antioxidant models. An abietane type diterpenoid sugiol, isolated from ethyl acetate extract of M. glyptostroboides cones, was analyzed for its antioxidant efficacy as reducing power ability and lipid peroxidation inhibition as well as its ability to scavenge free radicals such as 1,1-diphenyl-2-picryl hydrazyl, nitric oxide, superoxide and hydroxyl radicals. The sugiol showed significant and concentration-dependent antioxidant and free radical scavenging activities. Consequently, the sugiol exerted lipid peroxidation inhibitory effect by 76.5% as compared to α-tocopherol (80.13%) and butylated hydroxyanisole (76.59%). In addition, the sugiol had significant scavenging activities of 1,1-diphenyl-2-picryl hydrazyl, nitric oxide, superoxide and hydroxyl free radicals in a concentration-dependent manner by 78.83%, 72.42%, 72.99% and 85.04%, when compared to the standard compound ascorbic acid (81.69%, 74.62%, 73.00% and 73.79%) and α-tocopherol/butylated hydroxyanisole (84.09%, 78.61%, 74.45% and 70.02%), respectively. These findings justify the biological and traditional uses of M. glyptostroboides or its secondary metabolites as confirmed by its promising antioxidant efficacy. Copyright © 2014 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

  8. Protective effects of vitamin E on microcephaly in rats X-irradiated in utero: DNA, lipid peroxide and confronting cisternae

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Harumi; Iwasaki, Setsuo; Inomata, Kenichirou; Nasu, Fumio; Nishimura, Shigeru

    1986-06-01

    Fetuses from rats given either water or 0.03% D,L-..cap alpha..-tocopherol acetate (vitamin E) as a drinking fluid and X-irradiated with 100 rad on gestational day 13 were examined on gestational day 21. Mean cerebral weight which was significantly reduced by the X-irradiation was increased by vitamin E supplementation but the level did not reach that in sham-irradiated controls. Administration of vitamin E caused an increase in DNA concentration which was significantly reduced by X-irradiation with water treatment. An increase in the mean level of lipid peroxide formation was observed in the water-treated, X-irradiated group in the sample at zero time but not in the vitamin E-treated, X-irradiated group. In the cytoplasm of fetal cerebral neurons from X-irradiated dams with vitamin E supplementation, confronting cisternae were frequently observed between two nuclear envelopes. Confronting cisternae may be considered as a repair mechanism of vitamin E against X-irradiated neuronal damage in the fetal cerebrum. This study provides evidence of the protection by vitamin E of neuronal development in X-irradiated fetuses, through its antioxidant properties, against attacks by free radicals and/or lipid peroxide. 35 refs.; 3 figs.; 1 table.

  9. Preliminary study of cell metabolism, by use of NBT test, determination the intensity of lipid peroxidation and antioxidant activity

    Directory of Open Access Journals (Sweden)

    Diana BEI

    2009-05-01

    Full Text Available Otto Warburg, in the early part of the 20th century, originated a hypothesis, that the cause of cancer is primarily a defect in energy metabolism.A decrease in the capacity of mitochondria to reduce NAD(P, together with a decline in the NAD(PH/NAD(P redox couple, uncouples oxidative phosphorylation, lead to depletion of ATP and decrease the cell viability.Nitro-bleu tetrazolium have been used to assay cell proliferation and viability. The method to measure cell proliferation is based on enzymatic cleavage of the tetrazolium salts to a water-soluble formazan dye.Succinate-tetrazolium reductase, is an enzymatic sistem, which belongs to the respiratory chain of the mitochondria and it is active only in viable cells. The reagent diffuses into the cells and it is cleaved to formazan. The absorption change is measured and analysed.Free radicals such as superoxide, can cause a damage in cellular components, but several antioxidants inhibiting the lipid peroxidation and limiting the level of free radicals in cells.In the present study we had in view the proliferation and viability of leukemia cells during antineoplastic treatment along with the alteration of the serum level of malondialdehyde (MDA and ceruloplasmin (CP. With serum level of malondialdehyde we monitored the presence of the lipid peroxidation by the reactive oxygen species, and with the oxidized ceruloplasmin level in blood serum we evidenced the activity of antioxidant system in blood.

  10. Essential oil from lemon peels inhibit key enzymes linked to neurodegenerative conditions and pro-oxidant induced lipid peroxidation.

    Science.gov (United States)

    Oboh, Ganiyu; Olasehinde, Tosin A; Ademosun, Ayokunle O

    2014-01-01

    This study sought to investigate the effects of essential oil from lemon (Citrus limoni) peels on acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) activities in vitro. The essential oil was extracted by hydrodistillation, dried with anhydrous Na2SO4 and characterized using gas chromatography. Antioxidant properties of the oil and inhibition of pro-oxidant-induced lipid peroxidation in rats brain homogenate were also assessed. The essential oil inhibited AChE and BChE activities in a concentration-dependent manner. GC analysis revealed the presence of sabinene, limonene, α-pinene, β-pinene, neral, geranial, 1,8-cineole, linalool, borneol, α-terpineol, terpinen-4-ol, linalyl acetate and β-caryophyllene. Furthermore, the essential oil exhibited antioxidant activities as typified by ferric reducing property, Fe(2+)-chelation and radicals [DPPH, ABTS, OH, NO] scavenging abilities. The inhibition of AChE and BChE activities, inhibition of pro-oxidant induced lipid peroxidation and antioxidant activities could be possible mechanisms for the use of the essential oil in the management and prevention of oxidative stress-induced neurodegeneration.

  11. The effect of cadmium on phenylalanine ammonia lyase activity and lipid peroxidation in pepper (Capsicum annuum L. seedlings

    Directory of Open Access Journals (Sweden)

    Esra Koç

    2015-04-01

    Full Text Available In this study, the effect on differrent concentrations (20, 40, 80µM ve 100 µM CdCl2 of cadmium (CdCl2 on the activity of phenylalanine ammonia-lyase (PAL and lipid peroxidation amount in leaf and stem of Kahramanmaraş- Hot (Capsicum annum L. pepper seedlings were researched. Activity of phenylalanine ammonia-lyase (PAL, the first enzyme in the phenylpropanoid biosynthetic pathway, was increased at 2 and 4 days in KM-Hot plants exposed to CdCl2 stress. The highest PAL activity was detected in 20 μM CdCl2 application, on the four day after the application in the leaves of KM-Hot pepper. Moreover, it was observed that treatment of pepper with Cd led to an increased the rate of lipid peroxidation (which is indicated by increasing MDA content in the leaf and stem tissues. The highest MDA content was detected in 80 μM CdCl2 application, on the four day after the application in the leaf tissues. These results suggest that the activation of PAL may be associated with increased production of MDA

  12. The effect of ionizing radiation on the fatty acid composition of natural fats and on lipid peroxide formation

    International Nuclear Information System (INIS)

    Hammer, C.T.; Wills, E.D.

    1979-01-01

    The effects of irradiation doses of 200 to 1000 krad on the fatty acid composition of saturated and unsaturated natural food fats have been studied. Lard, coconut oil, corn oil, methyl linoleate and herring oil have been analysed before and after irradiation for lipid peroxide content and fatty acid composition. The effects of storage under varied conditions after irradiation have also been investigated. Irradiation doses of 200 to 1000 krad had little effect on the fatty acid compositions of saturated fats (lard and coconut oil) or of fats with a high antioxidant content (corn oil) but caused destruction of 98 per cent of the highly unsaturated acids (18:4, 20:5, 22:6) and 46 per cent of the diene acids (18:2) in herring oil. The destruction of the polyunsaturated fatty acids increased with increasing storage temperature and storage time. The destruction of polyunsaturated fatty acids was accompanied by an increase in lipid peroxide formation. It is considered that changes in fatty acid composition in natural foods after irradiation are important in consideration of the use of irradiation of food preservation. (author)

  13. Inhibition of oxidative stress and lipid peroxidation by anthocyanins from defatted Canarium odontophyllum pericarp and peel using in vitro bioassays.

    Directory of Open Access Journals (Sweden)

    Hock Eng Khoo

    Full Text Available Canarium odontophyllum, also known as CO, is a highly nutritious fruit. Defatted parts of CO fruit are potent sources of nutraceutical. This study aimed to determine oxidative stress and lipid peroxidation effects of defatted CO pericarp and peel extracts using in vitro bioassays. Cell cytotoxic effect of the CO pericarp and peel extracts were also evaluated using HUVEC and Chang liver cell lines. The crude extracts of defatted CO peel and pericarp showed cytoprotective effects in t-BHP and 40% methanol-induced cell death. The crude extracts also showed no toxic effect to Chang liver cell line. Using CD36 ELISA, NAD(+ and LDL inhibition assays, inhibition of oxidative stress were found higher in the crude extract of defatted CO peel compared to the pericarp extract. Hemoglobin and LDL oxidation assays revealed both crude extracts had significantly reduced lipid peroxidation as compared to control. TBARS values among defatted CO pericarp, peel, and cyanidin-3-glucoside showed no significant differences for hemoglobin and LDL oxidation assays. The protective effects of defatted CO parts, especially its peel is related to the presence of high anthocyanin that potentially offers as a pharmaceutical ingredient for cardioprotection.

  14. Fluorescent Lipids: Functional Parts of Fusogenic Liposomes and Tools for Cell Membrane Labeling and Visualization

    Directory of Open Access Journals (Sweden)

    Christian Kleusch

    2012-01-01

    Full Text Available In this paper a rapid and highly efficient method for controlled incorporation of fluorescent lipids into living mammalian cells is introduced. Here, the fluorescent molecules have two consecutive functions: First, they trigger rapid membrane fusion between cellular plasma membranes and the lipid bilayers of their carrier particles, so called fusogenic liposomes, and second, after insertion into cellular membranes these molecules enable fluorescence imaging of cell membranes and membrane traffic processes. We tested the fluorescent derivatives of the following essential membrane lipids for membrane fusion: Ceramide, sphingomyelin, phosphocholine, phosphatidylinositol-bisphosphate, ganglioside, cholesterol, and cholesteryl ester. Our results show that all probed lipids could more efficiently be incorporated into the plasma membrane of living cells than by using other methods. Moreover, labeling occurred in a gentle manner under classical cell culture conditions reducing cellular stress responses. Staining procedures were monitored by fluorescence microscopy and it was observed that sphingolipids and cholesterol containing free hydroxyl groups exhibit a decreased distribution velocity as well as a longer persistence in the plasma membrane compared to lipids without hydroxyl groups like phospholipids or other artificial lipid analogs. After membrane staining, the fluorescent molecules were sorted into membranes of cell organelles according to their chemical properties and biological functions without any influence of the delivery system.

  15. Circadian time structure of circulating plasma lipid peroxides, antioxidant enzymes and other small molecules in peptic ulcers.

    Science.gov (United States)

    Singh, Ranjana; Singh, Rajesh Kumar; Masood, Tariq; Tripathi, Anil Kumar; Mahdi, Abbas Ali; Singh, Raj Kumar; Schwartzkopff, Othild; Cornelissen, Germaine

    2015-12-07

    The circadian rhythm, as part of a broad time structure (chronome) of lipid peroxides and antioxidant defense mechanisms may relate to prevention, efficacy and management of preventive and curative chronotherapy. Fifty newly diagnosed patients with peptic ulcers, 30-45 years of age, and 60 age-matched clinically healthy volunteers were synchronized for one week with diurnal activity from about 06:00 to about 22:00 and nocturnal rest. Breakfast was served around 08:30, lunch around 13:30 and dinner around 20:30. Drugs known to affect the free-radical systems were not taken. Blood samples were collected at 6-hour intervals for 24h under standardized, presumably 24-hour synchronized conditions. Plasma lipid peroxides, in the form of malondialdehyde (MDA), blood superoxide dismutase (SOD), glutathione peroxide (GPx), glutathione reductase (GR), catalase (CAT) activities, and serum total protein, albumin, ascorbic acid, total serum cholesterol, and HDL-cholesterol concentrations were determined. By population-mean cosinor analysis, a marked circadian variation was demonstrated for all variables in healthy subjects and in ulcer patients (pascorbic acid, and HDL-C. They also had smaller circadian amplitude of SOD, CAT, GPx, GR, ascorbic acid, T-C, and HDL-C, but larger circadian amplitude of MDA and albumin. As compared to healthy subjects, the circadian acrophase of ulcer patients occurred later for MDA and GR and earlier for GPx. Mapping circadian rhythms, important chronome components that include trends with age and extra-circadian components characterizing antioxidants and pro-oxidants, is needed for exploring their putative role as markers in the treatment and management of peptic ulcers. Copyright © 2015. Published by Elsevier B.V.

  16. Mechanism for translocation of fluoroquinolones across lipid membranes

    DEFF Research Database (Denmark)

    Cramariuc, O.; Rog, T.; Javanainen, M.

    2012-01-01

    Classical atom-scale molecular dynamics simulations, constrained free energy calculations, and quantum mechanical (QM) calculations are employed to study the diffusive translocation of ciprofloxacin (CPFX) across lipid membranes. CPFX is considered here as a representative of the fluoroquinolone...... antibiotics class. Neutral and zwitterionic CPFX coexist at physiological pH, with the latter being predominant. Simulations reveal that only the neutral form permeates the bilayer, and it does so through a novel mechanism that involves dissolution of concerted stacks of zwitterionic ciprofloxacins....... Subsequent QM analysis of the observed molecular stacking shows the important role of partial charge neutralization in the stacks, highlighting how the zwitterionic form of the drug is neutralized for translocation. The findings propose a translocation mechanism in which zwitterionic CPFX molecules approach...

  17. Membrane Curvature and Lipid Composition Synergize To Regulate N-Ras Anchor Recruitment

    DEFF Research Database (Denmark)

    Larsen, Jannik B.; Kennard, Celeste; Pedersen, Søren L.

    2017-01-01

    Proteins anchored to membranes through covalently linked fatty acids and/or isoprenoid groups play crucial roles in all forms of life. Sorting and trafficking of lipidated proteins has traditionally been discussed in the context of partitioning to membrane domains of different lipid composition. We...

  18. Engineering lipid structure for recognition of the liquid ordered membrane phase

    International Nuclear Information System (INIS)

    Bordovsky, Stefan S.; Wong, Christopher S.; Bachand, George D.; Stachowiak, Jeanne C.; Sasaki, Darryl Y.

    2016-01-01

    The selective partitioning of lipid components in phase-separated membranes is essential for domain formation involved in cellular processes. Identifying and tracking the movement of lipids in cellular systems would be improved if we understood how to achieve selective affinity between fluorophore-labeled lipids and membrane assemblies. Furthermore, we investigated the structure and chemistry of membrane lipids to evaluate lipid designs that partition to the liquid ordered (L_o) phase. A range of fluorophores at the headgroup position and lengths of PEG spacer between the lipid backbone and fluorophore were examined. On a lipid body with saturated palmityl or palmitoyl tails, we found that although the lipid tails can direct selective partitioning to the L_o phase through favorable packing interactions, headgroup hydrophobicity can override the partitioning behavior and direct the lipid to the disordered membrane phase (L_d). The PEG spacer can serve as a buffer to mute headgroup–membrane interactions and thus improve L_o phase partitioning, but its effect is limited with strongly hydrophobic fluorophore headgroups. We present a series of lipid designs leading to the development of novel fluorescently labeled lipids with selective affinity for the L_o phase.

  19. Synthesis and phototoxicity of isomeric 7,9-diglutathione pyrrole adducts: Formation of reactive oxygen species and induction of lipid peroxidation

    Directory of Open Access Journals (Sweden)

    Liang Ma

    2015-09-01

    Full Text Available Pyrrolizidine alkaloids (PAs are hepatotoxic, genotoxic, and carcinogenic in experimental animals. Because of their widespread distribution in the world, PA-containing plants are probably the most common poisonous plants affecting livestock, wildlife, and humans. Upon metabolism, PAs generate reactive dehydro-PAs and other pyrrolic metabolites that lead to toxicity. Dehydro-PAs are known to react with glutathione (GSH to form 7-GSH-(+/−-6,7-dihydro-7-hydroxy-1-hydroxymethyl-5H-pyrrolizine (7-GS-DHP in vivo and in vitro and 7,9-diGS-DHP in vitro. To date, the phototoxicity of GS-DHP adducts has not been well studied. In this study, we synthesized 7-GS-DHP, a tentatively assigned 9-GS-DHP, and two enantiomeric 7,9-diGS-DHP adducts by reaction of dehydromonocrotaline with GSH. The two 7,9-diGS-DHPs were separated by high performance liquid chromatography (HPLC and their structures were characterized by 1H nuclear magnetic resonance (NMR and 1H–1H correlation spectroscopy (COSY NMR spectral analysis. Photoirradiation of 7-GS-DHP, 9-GS-DHP, and the two 7,9-diGS-DHPs as well as dehydromonocrotaline, dehydroheliotrine, and the 7-R enantiomer of DHP (DHR, by UVA light at 0 J/cm2, 14 J/cm2, and 35 J/cm2 in the presence of a lipid, methyl linoleate, all resulted in lipid peroxidation in a light dose-responsive manner. The levels of lipid peroxidation induced by the two isomeric 7,9-diGS-DHPs were significantly higher than that by 7-GS-DHP and 9-GS-DHP. When 7,9-diGS-DHP was irradiated in the presence of sodium azide (NaN3, the level of lipid peroxidation decreased; lipid peroxidation was enhanced when methanol was replaced by deuterated methanol. These results suggest that singlet oxygen is a product induced by the irradiation of 7,9-diGS-DHP. When irradiated in the presence of superoxide dismutase (SOD, the level of lipid peroxidation decreased, indicating that lipid peroxidation is also mediated by superoxide. These results indicate that lipid

  20. UVA Photoirradiation of Oxygenated Benz[a]anthracene and 3-Methylcholanthene - Generation of Singlet Oxygen and Induction of Lipid Peroxidation

    Directory of Open Access Journals (Sweden)

    Diógenes Herreño Sáenz

    2008-03-01

    Full Text Available Polycyclic aromatic hydrocarbons (PAHs are widespread genotoxic environmental pollutants and potentially pose a health risk to humans. Although the biological and toxicological activities, including metabolism, mutagenicity, and carcinogenicity, of PAHs have been thoroughly studied, their phototoxicity and photo-induced biological activity have not been well examined. We have long been interested in phototoxicity of PAHs and their derivatives induced by irradiation with UV light. In this paper we report the photoirradiation of a series of oxygenated benz[a]anthracene (BA and 3-methylcholanthene (3-MC by UVA light in the presence of a lipid, methyl linoleate. The studied PAHs include 2-hydroxy-BA (2-OH-BA, 3-hydroxy-BA (3-OH-BA, 5-hydroxymethyl-BA (5-CH2OH-BA, 7-hydroxymethyl-BA (7-CH2OH-BA, 12-hydroxymethyl-BA (12-CH2OH-BA, 7-hydroxymethyl-12-methyl-BA (7-CH2OH-12-MBA, 5-formyl-BA (5-CHO-BA, BA 5,6-cis-dihydrodiol (BA 5,6-cis-diol, 1-hydroxy-3- methylcholanthene (1-OH-3-MC, 1-keto-3-methylcholanthene (1-keto-3-MC, and 3-MC 1,2-diol. The results indicate that upon photoirradiation by UVA at 7 and 21 J/cm2, respectively all these compounds induced lipid peroxidation and exhibited a relationship between the dose of the light and the level of lipid peroxidation induced. To determine whether or not photoirradiation of these compounds by UVA light produces ROS, an ESR spin-trap technique was employed to provide direct evidence. Photoirradiation of 3-keto-3-MC by UVA (at 389 nm in the presence of 2,2,6,6-tetramethylpiperidine (TEMP, a specific probe for singlet oxygen, resulted in the formation of TEMPO, indicating that singlet oxygen was generated. These overall results suggest that UVA photoirradiation of oxygenated BA and 3-methylcholanthrene generates singlet oxygen, one of the reactive oxygen species (ROS, which induce lipid peroxidation.

  1. On ripples and rafts: Curvature induced nanoscale structures in lipid membranes

    International Nuclear Information System (INIS)

    Schmid, Friederike; Dolezel, Stefan; Meinhardt, Sebastian; Lenz, Olaf

    2014-01-01

    We develop an elastic theory that predicts the spontaneous formation of nanoscale structures in lipid bilayers which locally phase separate between two phases with different spontaneous monolayer curvature. The theory rationalizes in a unified manner the observation of a variety of nanoscale structures in lipid membranes: Rippled states in one-component membranes, lipid rafts in multicomponent membranes. Furthermore, we report on recent observations of rippled states and rafts in simulations of a simple coarse-grained model for lipid bilayers, which are compatible with experimental observations and with our elastic model

  2. Membrane-lipid therapy: A historical perspective of membrane-targeted therapies - From lipid bilayer structure to the pathophysiological regulation of cells.

    Science.gov (United States)

    Escribá, Pablo V

    2017-09-01

    Our current understanding of membrane lipid composition, structure and functions has led to the investigation of their role in cell signaling, both in healthy and pathological cells. As a consequence, therapies based on the regulation of membrane lipid composition and structure have been recently developed. This novel field, known as Membrane Lipid Therapy, is growing and evolving rapidly, providing treatments that are now in use or that are being studied for their application to oncological disorders, Alzheimer's disease, spinal cord injury, stroke, diabetes, obesity, and neuropathic pain. This field has arisen from relevant discoveries on the behavior of membranes in recent decades, and it paves the way to adopt new approaches in modern pharmacology and nutrition. This innovative area will promote further investigation into membranes and the development of new therapies with molecules that target the cell membrane. Due to the prominent roles of membranes in the cells' physiology and the paucity of therapeutic approaches based on the regulation of the lipids they contain, it is expected that membrane lipid therapy will provide new treatments for numerous pathologies. The first on-purpose rationally designed molecule in this field, minerval, is currently being tested in clinical trials and it is expected to enter the market around 2020. However, it seems feasible that during the next few decades other membrane regulators will also be marketed for the treatment of human pathologies. This article is part of a Special Issue entitled: Membrane Lipid Therapy: Drugs Targeting Biomembranes edited by Pablo V. Escribá. Copyright © 2017. Published by Elsevier B.V.

  3. Bioactive potential of Vitis labrusca L. grape juices from the Southern Region of Brazil: phenolic and elemental composition and effect on lipid peroxidation in healthy subjects.

    Science.gov (United States)

    Toaldo, Isabela Maia; Cruz, Fernanda Alves; Alves, Tatiana de Lima; de Gois, Jefferson Santos; Borges, Daniel L G; Cunha, Heloisa Pamplona; da Silva, Edson Luiz; Bordignon-Luiz, Marilde T

    2015-04-15

    Grapes are rich in polyphenols with biologically active properties. Although the bioactive potential of grape constituents are frequently reported, the effects of Brazilian Vitis labrusca L. grape juices ingestion have not been demonstrated in humans. This study identified the phenolic and elemental composition of red and white grape juices and the effect of organic and conventional red grape juice consumption on lipid peroxidation in healthy individuals. Concentrations of anthocyanins, flavanols and phenolic acids and the in vitro antioxidant activity were significantly higher in the organic juice. The macro-elements K, Ca, Na and Mg were the most abundant minerals in all juices. The acute consumption of red grape juices promoted significant decrease of lipid peroxides in serum and TBARS levels in plasma. It is concluded that red V. labrusca L. grape juices produced in Southern Brazil showed lipid peroxidation inhibition abilities in healthy subjects, regardless of the cultivation system. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Structural properties of lipid reconstructs and lipid composition of normotensive and hypertensive rat vascular smooth muscle cell membranes

    Directory of Open Access Journals (Sweden)

    T.R. Oliveira

    2009-09-01

    Full Text Available Multiple cell membrane alterations have been reported to be the cause of various forms of hypertension. The present study focuses on the lipid portion of the membranes, characterizing the microviscosity of membranes reconstituted with lipids extracted from the aorta and mesenteric arteries of spontaneously hypertensive (SHR and normotensive control rat strains (WKY and NWR. Membrane-incorporated phospholipid spin labels were used to monitor the bilayer structure at different depths. The packing of lipids extracted from both aorta and mesenteric arteries of normotensive and hypertensive rats was similar. Lipid extract analysis showed similar phospholipid composition for all membranes. However, cholesterol content was lower in SHR arteries than in normotensive animal arteries. These findings contrast with the fact that the SHR aorta is hyporeactive while the SHR mesenteric artery is hyperreactive to vasopressor agents when compared to the vessels of normotensive animal strains. Hence, factors other than microviscosity of bulk lipids contribute to the vascular smooth muscle reactivity and hypertension of SHR. The excess cholesterol in the arteries of normotensive animal strains apparently is not dissolved in bulk lipids and is not directly related to vascular reactivity since it is present in both the aorta and mesenteric arteries. The lower cholesterol concentrations in SHR arteries may in fact result from metabolic differences due to the hypertensive state or to genes that co-segregate with those that determine hypertension during the process of strain selection.

  5. Ionic protein-lipid interaction at the plasma membrane: what can the charge do?

    Science.gov (United States)

    Li, Lunyi; Shi, Xiaoshan; Guo, Xingdong; Li, Hua; Xu, Chenqi

    2014-03-01

    Phospholipids are the major components of cell membranes, but they have functional roles beyond forming lipid bilayers. In particular, acidic phospholipids form microdomains in the plasma membrane and can ionically interact with proteins via polybasic sequences, which can have functional consequences for the protein. The list of proteins regulated by ionic protein-lipid interaction has been quickly expanding, and now includes membrane proteins, cytoplasmic soluble proteins, and viral proteins. Here we review how acidic phospholipids in the plasma membrane regulate protein structure and function via ionic interactions, and how Ca(2+) regulates ionic protein-lipid interactions via direct and indirect mechanisms. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. First integrals of the axisymmetric shape equation of lipid membranes

    Science.gov (United States)

    Zhang, Yi-Heng; McDargh, Zachary; Tu, Zhan-Chun

    2018-03-01

    The shape equation of lipid membranes is a fourth-order partial differential equation. Under the axisymmetric condition, this equation was transformed into a second-order ordinary differential equation (ODE) by Zheng and Liu (Phys. Rev. E 48 2856 (1993)). Here we try to further reduce this second-order ODE to a first-order ODE. First, we invert the usual process of variational calculus, that is, we construct a Lagrangian for which the ODE is the corresponding Euler–Lagrange equation. Then, we seek symmetries of this Lagrangian according to the Noether theorem. Under a certain restriction on Lie groups of the shape equation, we find that the first integral only exists when the shape equation is identical to the Willmore equation, in which case the symmetry leading to the first integral is scale invariance. We also obtain the mechanical interpretation of the first integral by using the membrane stress tensor. Project supported by the National Natural Science Foundation of China (Grant No. 11274046) and the National Science Foundation of the United States (Grant No. 1515007).

  7. Comprehensive metabolomics identified lipid peroxidation as a prominent feature in human plasma of patients with coronary heart diseases

    Directory of Open Access Journals (Sweden)

    Jianhong Lu

    2017-08-01

    Full Text Available Coronary heart disease (CHD is a complex human disease associated with inflammation and oxidative stress. The underlying mechanisms and diagnostic biomarkers for the different types of CHD remain poorly defined. Metabolomics has been increasingly recognized as an enabling technique with the potential to identify key metabolomic features in an attempt to understand the pathophysiology and differentiate different stages of CHD. We performed comprehensive metabolomic analysis in human plasma from 28 human subjects with stable angina (SA, myocardial infarction (MI, and healthy control (HC. Subsequent analysis demonstrated a uniquely altered metabolic profile in these CHD: a total of 18, 37 and 36 differential metabolites were identified to distinguish SA from HC, MI from SA, and MI from HC groups respectively. Among these metabolites, glycerophospholipid (GPL metabolism emerged as the most significantly disturbed pathway. Next, we used a targeted metabolomic approach to systematically analyze GPL, oxidized phospholipid (oxPL, and downstream metabolites derived from polyunsaturated fatty acids (PUFAs, such as arachidonic acid and linoleic acid. Surprisingly, lipids associated with lipid peroxidation (LPO pathways including oxidized PL and isoprostanes, isomers of prostaglandins, were significantly elevated in plasma of MI patients comparing to HC and SA, consistent with the notion that oxidative stress-induced LPO is a prominent feature in CHD. Our studies using the state-of-the-art metabolomics help to understand the underlying biological mechanisms involved in the pathogenesis of CHD; LPO metabolites may serve as potential biomarkers to differentiation MI from SA and HC. Keywords: Metabolomics, Lipid peroxidation, Lipidomics, Myocardial infarction, Isoprostanes, Coronary heart disease (CHD

  8. Monoolein lipid phases as incorporation and enrichment materials for membrane protein crystallization.

    Directory of Open Access Journals (Sweden)

    Ellen Wallace

    Full Text Available The crystallization of membrane proteins in amphiphile-rich materials such as lipidic cubic phases is an established methodology in many structural biology laboratories. The standard procedure employed with this methodology requires the generation of a highly viscous lipidic material by mixing lipid, for instance monoolein, with a solution of the detergent solubilized membrane protein. This preparation is often carried out with specialized mixing tools that allow handling of the highly viscous materials while minimizing dead volume to save precious membrane protein sample. The processes that occur during the initial mixing of the lipid with the membrane protein are not well understood. Here we show that the formation of the lipidic phases and the incorporation of the membrane protein into such materials can be separated experimentally. Specifically, we have investigated the effect of different initial monoolein-based lipid phase states on the crystallization behavior of the colored photosynthetic reaction center from Rhodobacter sphaeroides. We find that the detergent solubilized photosynthetic reaction center spontaneously inserts into and concentrates in the lipid matrix without any mixing, and that the initial lipid material phase state is irrelevant for productive crystallization. A substantial in-situ enrichment of the membrane protein to concentration levels that are otherwise unobtainable occurs in a thin layer on the surface of the lipidic material. These results have important practical applications and hence we suggest a simplified protocol for membrane protein crystallization within amphiphile rich materials, eliminating any specialized mixing tools to prepare crystallization experiments within lipidic cubic phases. Furthermore, by virtue of sampling a membrane protein concentration gradient within a single crystallization experiment, this crystallization technique is more robust and increases the efficiency of identifying productive

  9. Ascorbic acid improves the antioxidant activity of European grape juices by improving the juices' ability to inhibit lipid peroxidation of human LDL in vitro

    DEFF Research Database (Denmark)

    Landbo, Anne-Katrine Regel; Meyer, Anne Boye Strunge

    2001-01-01

    . Red grape juice concentrate inhibited lipid peroxidation of LDL by prolonging the lag phase by 2.7 times relative to a control when evaluated at a total phenolic concentration of 10 muM gallic acid equivalents (GAE). Both red grape juices tested blocked lipid peroxidation of LDL at 20 muM GAE. White.......96, P acid alone did not exert antioxidant activity towards LDL, but combinations of 5 muM ascorbic acid with 5 muM GAE juice phenols eliminated the prooxidant activity of white grape juice, and significantly...

  10. Influence of separate and combined impact both of radiation and chemical factors on state of lipid peroxide oxidation system and antioxidant protection at pregnant rats

    International Nuclear Information System (INIS)

    Danil'chik, V.S.; Spivak, L.V.; Kolb, V.G.; Zubovskaya, E.T.; Rogov, Yu.I.

    2000-01-01

    Influence of low dozed ionizing irradiation and chemical toxicant was studied both under separate and combined action in the process of pregnancy. The lipid peroxidation (LPO) indices and antioxidant protection (AOP) parameters of females rats were studied. The result received proved that irradiation during pregnancy induced activation both of lipids free radical oxidation and of antioxidant protection in female rats. Chemical toxicants introduction resulted in shifts on the LPO-AOP system the hydrogen peroxide blood level increasing and the antioxidants ones reducing. Combined action of both factors led to development of a new level of LPO-AOP

  11. Lipid peroxide levels of serum lipoprotein fractions of diabetic patients with angiopathy and 60Co-irradiated rabbit

    International Nuclear Information System (INIS)

    Tsunekawa, Hiroshi

    1982-01-01

    For a better understanding of the relationship between lipid peroxide (LPO) and vascular diseases, the author determined LPO levels and lipid contents of serum lipoprotein fractions of diabetics with angiopathy. The LPO level in high density lipoprotein (HDL) fraction of diabetic serum was significantly higher than that of normal serum whereas no significant increase was observed in the levels of very low density lipoprotein (VLDL) and low density lipoprotein (LDL) fractions of diabetic serum. As to the ratios of LPO to total lipids in these lipoprotein fractions, it was found that the ratio in HDL fraction of the diabetics was markedly higher than that of the normals. These results suggest that the increase in LPO levels in the sera of diabetic patiens is due to that in HDL fraction. To study further this problem, the author employed 60 Co-irradiated rabbit as a model, since it was already reported that radiation affects lipid metabolism and LPO formation, and that it induces the development of atherosclerosis. Upon irradiation with 60 Co ranging from 100R to 700R, serum LPO level of rabbit was significantly increased. Although elevation of LPO level was found in each serum lipoprotein fraction of VLDL, LDL and HDL, LPO level per lipid content was significantly increased only in HDL fraction. In the irradiated rabbit, significant elevation of the level of LPO was also observed in the liver, while no significant increase was found in the kidney and spleen. These results indicate that high level of LPO observed in the serum of irradiated rabbit would be the reflection of the increased LPO in the liver. (J.P.N.)

  12. Lipid peroxide levels of serum lipoprotein fractions of diabetic patients with angiopathy and /sup 60/Co-irradiated rabbit

    Energy Technology Data Exchange (ETDEWEB)

    Tsunekawa, Hiroshi [Nagoya Univ. (Japan). Faculty of Medicine

    1982-09-01

    For a better understanding of the relationship between lipid peroxide (LPO) and vascular diseases, the author determined LPO levels and lipid contents of serum lipoprotein fractions of diabetics with angiopathy. The LPO level in high density lipoprotein (HDL) fraction of diabetic serum was significantly higher than that of normal serum whereas no significant increase was observed in the levels of very low density lipoprotein (VLDL) and low density lipoprotein (LDL) fractions of diabetic serum. As to the ratios of LPO to total lipids in these lipoprotein fractions, it was found that the ratio in HDL fraction of the diabetics was markedly higher than that of the normals. These results suggest that the increase in LPO levels in the sera of diabetic patients is due to that in HDL fraction. To study further this problem, the author employed /sup 60/Co-irradiated rabbit as a model, since it was already reported that radiation affects lipid metabolism and LPO formation, and that it induces the development of atherosclerosis. Upon irradiation with /sup 60/Co ranging from 100R to 700R, serum LPO level of rabbit was significantly increased. Although elevation of LPO level was found in each serum lipoprotein fraction of VLDL, LDL and HDL, LPO level per lipid content was significantly increased only in HDL fraction. In the irradiated rabbit, significant elevation of the level of LPO was also observed in the liver, while no significant increase was found in the kidney and spleen. These results indicate that high level of LPO observed in the serum of irradiated rabbit would be the reflection of the increased LPO in the liver.

  13. Effects of dietary ascorbic acid supplementation on lipid peroxidation and the lipid content in the liver and serum of magnesium-deficient rats.

    Science.gov (United States)

    Akiyama, Satoko; Uehara, Mariko; Katsumata, Shin-ichi; Ihara, Hiroshi; Hashizume, Naotaka; Suzuki, Kazuharu

    2008-12-01

    We investigated the effects of ascorbic acid (AsA) supplementation on lipid peroxidation and the lipid content in the liver and serum of magnesium (Mg)-deficient rats. Eighteen 3-week-old male Sprague-Dawley strain rats were divided into 3 groups and maintained on a control diet (C group), a low-Mg diet (D group), or a low-Mg diet supplemented with AsA (DA group) for 42 d. At the end of this period, the final body weight, weight gain, and serum Mg concentrations were significantly decreased in the Mg-deficient rats. Further, dietary AsA supplementation had no effect on the growth, serum Mg concentration, Mg absorption, and Mg retention. The serum concentration of AsA was significantly lower in the D group than in the C group but was unaltered in the DA group. The levels of phosphatidylcholine hydroperoxide (PCOOH) in the serum and of triglycerides (TGs) and total cholesterol (TC) in the serum and liver were significantly higher in the D group than in the C group. The serum PCOOH, liver TG, and liver TC levels were decreased in the DA group. These results indicate that Mg deficiency increases the AsA requirement of the body and that AsA supplementation normalizes the serum levels of PCOOH and the liver lipid content in Mg-deficient rats, without altering the Mg status.

  14. Membrane interaction of antimicrobial peptides using E. coli lipid extract as model bacterial cell membranes and SFG spectroscopy.

    Science.gov (United States)

    Soblosky, Lauren; Ramamoorthy, Ayyalusamy; Chen, Zhan

    2015-04-01

    Supported lipid bilayers are used as a convenient model cell membrane system to study biologically important molecule-lipid interactions in situ. However, the lipid bilayer models are often simple and the acquired results with these models may not provide all pertinent information related to a real cell membrane. In this work, we use sum frequency generation (SFG) vibrational spectroscopy to study molecular-level interactions between the antimicrobial peptides (AMPs) MSI-594, ovispirin-1 G18, magainin 2 and a simple 1,2-dipalmitoyl-d62-sn-glycero-3-phosphoglycerol (dDPPG)/1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoglycerol (POPG) bilayer. We compared such interactions to those between the AMPs and a more complex dDPPG/Escherichia coli (E. coli) polar lipid extract bilayer. We show that to fully understand more complex aspects of peptide-bilayer interaction, such as interaction kinetics, a heterogeneous lipid composition is required, such as the E. coli polar lipid extract. The discrepancy in peptide-bilayer interaction is likely due in part to the difference in bilayer charge between the two systems since highly negative charged lipids can promote more favorable electrostatic interactions between the peptide and lipid bilayer. Results presented in this paper indicate that more complex model bilayers are needed to accurately analyze peptide-cell membrane interactions and demonstrates the importance of using an appropriate lipid composition to study AMP interaction properties. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  15. Changes in lipid membrane mechanics induced by di- and tri-phenyltins

    DEFF Research Database (Denmark)

    Przybyło, Magda; Drabik, Dominik; Szostak, Kamila

    2017-01-01

    properties of biological membranes. It was found that the membrane/water partition coefficient equals 4, a value significantly higher than octanol/water partition coefficient. In addition, the effect of di- and tri-phenyltin chlorides on the mechanics of model lipid membranes was measured for the first time...

  16. Individual and Combined Effects of Fumonisin B1, Deoxynivalenol and Zearalenone on the Hepatic and Renal Membrane Lipid Integrity of Rats

    Directory of Open Access Journals (Sweden)

    András Szabó

    2017-12-01

    Full Text Available (1 Background and (2 Methods: A 14-day in vivo, multitoxic (pure mycotoxins rat experiment was conducted with zearalenone (ZEA; 15 μg/animal/day, deoxynivalenol (DON; 30 μg/animal/day and fumonisin B1 (FB1; 150 μg/animal/day, as individual mycotoxins, binary (FD, FZ and DZ and ternary combinations (FDZ, via gavage in 1 mL water boluses. (3 Results: Body weight was unaffected, while liver (ZEA↑ vs. DON and kidney weight (ZEA↑ vs. FDZ increased. Hepatocellular membrane lipid fatty acids (FAs referred to ceramide synthesis disturbance (C20:0, C22:0, and decreased unsaturation (C22:5 n3 and unsat. index, mainly induced by DON and to a lesser extent by ZEA. The DON-FB1 interaction was additive on C20:0 in liver lipids. In renal phospholipids, ZEA had the strongest effect on the FA profile, affecting the saturated (C18:0 and many n6 FAs; ZEA was in an antagonistic relationship with FB1 (C18:0 or DON (C18:2 n6, C20:1 n9. Hepatic oxidative stress was the most expressed in FD (reduced glutathione and glutathione peroxidase, while the nephrotoxic effect was further supported by lipid peroxidation (malondialdehyde in the DON treatment. (4 Conclusions: In vivo study results refer to multiple mycotoxin interactions on membrane FAs, antioxidants and lipid peroxidation compounds, needing further testing.

  17. Yeast lipids can phase separate into micrometer-scale membrane domains

    DEFF Research Database (Denmark)

    Klose, Christian; Ejsing, Christer S; Garcia-Saez, Ana J

    2010-01-01

    The lipid raft concept proposes that biological membranes have the potential to form functional domains based on a selective interaction between sphingolipids and sterols. These domains seem to be involved in signal transduction and vesicular sorting of proteins and lipids. Although there is bioc......The lipid raft concept proposes that biological membranes have the potential to form functional domains based on a selective interaction between sphingolipids and sterols. These domains seem to be involved in signal transduction and vesicular sorting of proteins and lipids. Although...... there is biochemical evidence for lipid raft-dependent protein and lipid sorting in the yeast Saccharomyces cerevisiae, direct evidence for an interaction between yeast sphingolipids and the yeast sterol ergosterol, resulting in membrane domain formation, is lacking. Here we show that model membranes formed from yeast...... total lipid extracts possess an inherent self-organization potential resulting in Ld-Lo phase coexistence at physiologically relevant temperature. Analyses of lipid extracts from mutants defective in sphingolipid metabolism as well as reconstitution of purified yeast lipids in model membranes of defined...

  18. Andrographolide Ameliorates Beta-Naphthoflavone-Induced CYP1A Enzyme Activity and Lipid Peroxidation in Hamsters with Acute Opisthorchiasis.

    Science.gov (United States)

    Udomsuk, Latiporn; Chatuphonprasert, Waranya; Jarukamjorn, Kanokwan; Sithithaworn, Paiboon

    2016-01-01

    Opisthorchis viverrini (OV) infection generates oxidative stress/free radicals and is considered as a primary cause ofcholangiocarcinoma since it primarily triggers sclerosing cholangitis. In this study, the impacts of andrographolide on acute opisthorchaisis in β-naphthoflavone (BNF)-exposed hamsters were investigated. Ethoxyresorufin O-deethylase (EROD) and methoxyresorufin O-demethylase (MROD) activities and Thiobarbituric acid reaction substances (TBARS) assay of andrographolide in acute opisthorchiasis in the BNF-exposed hamsters were assessed. The results showed that andrographolide ameliorated the hepatic CYP1A1 and CYP1A2 activities by decreases of the specific enzymatic reactions of EROD and MROD, respectively, in the BNF-exposed hamsters. Moreover, andrographolide lowered the formation of malondialdehyde in the livers and brains of the hamsters. These observations revealed the promising chemo-protective and antioxidant activities of andrographolide via suppression of the specific EROD and MROD reactions and lipid peroxidation against acute opisthorchiasis in the BNF-exposed hamsters.

  19. Effect of acute sup(60)Co-gamma-irradiation on the in vivo lipid peroxidation in experimental animals

    International Nuclear Information System (INIS)

    Ronai, Eva; Benkoe, Gy.

    1984-01-01

    The effect of sublethal (6.0 Gy) and LDsub(50/30) (9.0 Gy) doses of sup(60)Co-gamma-irradiation on malondialdehyde (MDA) level was studied in rats. The findings suggest that in the organs investigated (brain, liver, spleen, kidneys, testicles, stomach, small intestines) acute sup(60)Co gamma-irradiation increased the formation of MDA, the main product of lipid peroxidation, in a time-related manner to an extent characteristic of the organ investigated. Differences in the degree and temporal development of the changes allow some conclusions as to the radiosensitivity of individual organs. On this basis it can be assumed that the increase in MDA level caused by irradiation considerably contributes to the development of certain symptoms of radiation sickness. (author)

  20. The effect of different levels of garlic extract administration at various time periods on the extent of serumic lipid peroxidation in laying hens

    Directory of Open Access Journals (Sweden)

    saeed rasoulinejad

    2013-02-01

    Full Text Available