• Molecules and Cells
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• v.19 no.3
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• pp.356-364
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• 2005

Intramolecular excimer formation of 1,3-di(1-pyrenyl) propane(Py-3-Py) and fluorescence polarization of 1,6-diphenyl-1,3,5-hexatriene (DPH) were used to evaluate the effect of ethanol on the rate and range of lateral and rotational mobilities of bulk bilayer structures of synaptosomal plasma membrane vesicles (SPMVs) from the bovine cerebral cortex. Ethanol increased the excimer to monomer fluorescence intensity ratio (I'/I) of Py-3-Py in the SPMVs. Selective quenching of both DPH and Py-3-Py by trinitrophenyl groups was used to examine the range of transbilayer asymmetric rotational mobility and the rate and range of transbilayer asymmetric lateral mobility of SPMVs. Ethanol increased the rotational and lateral mobility of the outer monolayer more than of the inner one. Thus ethanol has a selective fluidizing effect within the transbilayer domains of the SPMVs. Radiationless energy transfer from the tryptophans of membrane proteins to Py-3-Py was used to examine both the effect of ethanol on annular lipid fluidity and protein distribution in the SPMVs. Ethanol increased annular lipid fluidity and also caused membrane proteins to cluster. These effects on neuronal membranes may be responsible for some, though not all, of the general anesthetic actions of ethanol.

• Journal of Photoscience
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• v.4 no.2
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• pp.41-48
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• 1997

The plasma membrane and microsomes, isolated from the cells treated with hematoporphyrm derivative (HpD) for 1 and 24 h, accumulated the aggregated porphyrin. The quantity of aggregated porphyrin was same in the plasma membrane and microsomes after isolating them from cells treated with HpD for 1 h whereas the microsomes accumulated higher quantity of aggregated porphyrin when cells were treated with HpD for 24 h. Photodynamic action of aggregated porphyrin on plasma membrane and microsomes was investigated using lipid specific fluorescent probes: 1,6-diphenyl-1,3,5-hexatrine (DPH) and 1-(4-trimethylammonium), 6-diphenyl-1,3,5-hexatrine(TMA-DPH). The time dependent anisotropy of these probes in the membranes was measured and the decay of anisotropy was analyzed using wobbling in cone model. Upon irradiation both the plasma membrane and the microsomes showed an increase in the limiting anis~)tropy and order parameter and a decrease in the cone angle of the lipid probes. The increase in the limiting anisotropy was pronounced in membranes isolated from the cells treated with HpD for 24 h. Photoinduced change in the limiting anisotropy was dependent on the duration of incubation of cells with HpD before isolating the membranes. In both the membranes. the membrane core was affected more as compared to the outer leaflet. In addition to the structural changes, a decrease in Na$^+$-K$^+$-ATPase and NADPH cyt c reductase activity was also observed upon irradiation of HpD treated cells. Inhibition in NADPH cyt c reductase was more when cells were treated with HpD for 24 h, however, Na$^+$-K$^+$-ATPase activity did not depend on the duration of the treatment of cells with HpD before irradiation. Our results suggest that the extent of photoinduced perturbations in the membranes varies as a function of duration of the treatment of cells with HpD and the membrane core is more susceptible to the photodynamic action of aggregated porphyrin.

• Archives of Pharmacal Research
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• v.13 no.1
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• pp.64-68
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• 1990

The stabilization effect of .alpha.-tocopherol incorporated into liposomal phospholipid membrane was investigated by fluorospectrophotometry and UV-visible spectretarded by the presence of .alpha.-tocopherol in the bilayer of liposomal phospholipid membrane relative to cholesterol-containing liposomes and pure phospholipid liposomes. .alpha.-tocopherol-containing liposomes prolonged the oxidation of liposomes-embedded heme as those of cholesterol-containing liposomes and pure phospholipid liposomes. Thus .alpha.-tocopherol-containing liposomes may be useful for the carrier systems of nutrients and drugs to phospholipid bilayer and stabilized liposomes.

• Journal of Microbiology
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• v.33 no.3
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• pp.228-233
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• 1995

As S. epidermidis cell was fractionated into cell wall, cell membrane, and cytoplasm, the cell membrane proved to be the most efficient absorbent for lead ion. Utrasonication was effective, when the cells were treated during their exponential growth. The amount of the lead ion adsorbed in cell membrane decreased as hydrogen ion concentration of solution increased. Protein purified from the cell membrane showed higher adsorption capacity for the lead ion than peptidoglycan, teichoic acid from cell wall, or cell membrane lipid. Modification of carboxyl groups in the membrane protein with ethylenediamine and 1-ethyl-3-carbodiimide hydrochloride resulted in a considerable decrease of lead ion adsorption capability, suggesting that the main binding site for lead ion was the carboxyl groups of protein in cell membrane.

• Bulletin of the Korean Chemical Society
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• v.17 no.3
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• pp.279-284
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• 1996

Decay of the spin label attached to cytochrome c or to stearic acid has been measured by electron paramagnetic resonance (EPR) spectroscopy to monitor membrane oxidation induced by cytochrome c-membrane interaction. Binding of cytochrome c sequestered the acidic phospholipids and membrane oxidation was efficient in the order linoleic oleic>stearic acid for a fatty acid chain in the acidic phospholipids. The spin label on cyt c was destroyed at pH 7 whereas that on stearic acid embedded in the membrane was destroyed at pH 4, presumably due to different modes of cyt c-membrane interaction depending on pH. Interestingly, cyt c also interacts with phosphatidylethanolamine, an electrically neutral phospholipid, to cause rapid membrane oxidation. Both EPR and fluorescence measurements indicated that electrostatic interaction is at least partially responsible for the process.

• Journal of Animal Science and Technology
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• v.49 no.6
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• pp.729-736
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• 2007

The objective of this study was to investigate the anti-oxidative effects of pyruvate, taurine and melatonin on sperm characteristics(motility, membrane integrity) and lipid peroxidation(LPO) for in vitro storage of boar semen. Semen was treated with various antioxidants such as pyruvate(1mM), taurine(50mM) and melatonin(100nM) with or without 100uM H2O2. Antioxidant treatments were significantly increased the sperm motility when compare to control group in all incubation periods(P≤0.05). Hypoosmotic swelling test(HOST), membrane integrity was similar to the result of motility. In lipid peroxidation measurement by TBA reactions of spermatozoal plasma membrane, malondialdehyde(MDA) level in control and antioxidant treatments were lower than those of antioxidant plus H2O2 or H2O2 treatment for 3 to 6 h incubation period. Relationships of evaluation methods for sperm viability were investigated by motility, membrane integrity and lipid peroxidation. Among evaluation methods, LPO vs motility and membrane integrity vs LPO were negatively correlated(－0.23~－0.92 and －0.68~－0.85), but membrane integrity vs motility was positively correlated (0.53~0.94) in all treatments. These experiments indicate that supplementation of antioxidant to the semen extender can increase the sperm motility and membrane integrity and decrease the lipid peroxidation of spermatozoal plasma membrane. The HOST might be utilized to evaluate the sperm quality instead of lipid peroxidation or motility.

• Bulletin of the Korean Chemical Society
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• v.28 no.10
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• pp.1756-1762
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• 2007

Envelope proteins of virus contain a segment of hydrophobic amino acids, called as fusion peptide, which triggers membrane fusion by insertion into membrane and perturbation of lipid bilayer structure. Potential fusion peptide sequences have been identified in the middle of L or M proteins or at the N-terminus of S protein in the envelope of human hepatitis B virus (HBV). Two 16-mer peptides representing the N-terminal fusion peptide of the S protein and the internal fusion peptide in L protein were synthesized, and their membrane disrupting activities were characterized. The internal fusion peptide in L protein showed higher activity of liposome leakage and hemolysis of human red blood cells than the N-terminal fusion peptide of S protein. Also, the membrane disrupting activity of the extracellular domain of L protein significantly increased when the internal fusion peptide region was exposed to N-terminus by the treatment of V8 protease. These results indicate that the internal fusion peptide region of L protein could activate membrane fusion when it is exposed by proteolysis.

• Journal of Nutrition and Health
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• v.27 no.1
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• pp.46-52
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• 1994

Recently it is reported that RBC membrane fluidity decreases and RBC calcium levels increase with age. The aim of this study was to analyze changes in lipid and calcium metabolism with age, and to seek relationship of diet and metabolism. With clinically normal Korean adults(male 60, female 63), this study was carried out in three phases : 1) to analyze fatty acid percentage of RBC membrane, 2) to analyze calcium levels of RBC with age, and 3) to compare the effects of dietary fatty acid intake on blood fatty acid profiles. The results are as follows : The P/S ratio of RBC membrane fatty acid decreased with age. The RBC calcium content increased according to age, with women having a higher level than men. The higher intake groups of linolenic acid(C18:3) has statistically higher serum linolenic acid levels. But dietary effects of membrane fatty acid were not found. Therefore, the further research to seek the possible relationship of diet and membrane fatty acid should be continued.

• Preventive Nutrition and Food Science
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• v.1 no.1
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• pp.143-150
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• 1996

The membrane fatty acid composition of tumor cell can be modified either in cell by altering the lipid composition of the medium of during growth in animals by changing the dietaty fat composition. These modifications are associated with changes in membrane physical properties and certain cellular functions, including carrier-mediated transport and enzyme contained within the membrane. Such effects influence the transport of nutrients and chemotherapeutic agents in cancer cells .Fatty acid modification also can enhance the sensitivity of the neoplastic cell to chemotherapy. The alteration in plasma membrane composition will be affected through dietary supplementations and the potential value to cancer patients could be a better understanding of the effects of diet on responsiveness of neoplasms to chemotherapy, i.e. cancer patients' chances for a "cure" can be improved by diet changes prior to treatment.

• Korean Journal of Veterinary Research
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• v.35 no.4
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• pp.699-712
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• 1995

The present study, to evaluate the effect of vitamin E on the oxidative stress in STZ-treated rat and BB rat, was investigated the biochemical enzyme activity in the serum, and malondialdehyde and carbonyl group in the RBC membrane, liver and microsomal fraction after vitamin E and/ or insulin treatment. Results obtained through the experiments were summarized as follows; 1. Effect of vitamin E and/or insulin treatment in STZ-treated rat 1) Lipid peroxidation level in RBC membrane, liver and microsomal fraction was significantly decreased in vi. tamin E and/or insulin treatment group, and especially more significantly decreased in vitamin E with insulin treated group. 2) Protein oxidation level in RBC membrane, liver and microsomal fraction was significantly decreased in vitamin E and/or insulin treatment group. And it was especially more significantly decreased in RBC membrane and liver of vitamin E with insulin treated group. 3) In the enzyme activity in the serum, the activity of AST and ALT was not altered in all experimental group. The increased ALP activity in STZ-treated group was significantly decreased in insulin treated group and vitamin E with insulin treated group. 4) Decreased level of albumin and creatinine after STZ treatment was significantly increased in vitamin E and/or insulin treated group. 5) Level of glucose, cholesterol and triacylglycerol in serum: Glucose level was not significantly different in vitamin E treated group compared to STZ control group. But it was significantly different in the insulin treated group and vitamin E with insulin treated group compared to STZ control group. The cholesterol content in the serum was significantly increased in STZ control group compared to normal control group. And except low dose vitamin E treatment group, it was significantly decreased in vitamin E and/or insulin treated group compared to STZ control group. The triacylglycerol content in the serum was significantly decreased in STZ control group and increased in high dose vitamin E treated group and vitamin E with insulin treated group. But it was not significantly different in low dose vitamin E treated group and insulin treated group compared to STZ control group. 2. Effect of vitamin E and/or insulin treatment in BB rat 1) Lipid peroxidation level in liver was decreased by vitamin E with insulin treatment compared to insulin treatment. But it was not different in microsomal fractions. 2) Protein oxidation level in liver and microsomal fraction was decreased by vitamin E with insulin treatment compared to insulin treatment only in microsomal fractions. These results suggest that the combination treatment of vitamin E and insulin could prevent the oxidative change of lipid and protein of the RBC membrane, liver and microsomal fraction in STZ-treated rats and BB rats.