• Proceedings of the Korean Society of Applied Pharmacology
• /
• 1996.04a
• /
• pp.286-286
• /
• 1996

In order to elucidate the mechanism of action of transdermal absorption-enhancing compounds, i.e., pyrrolidone derivatives (2-pyrrolidone, 1-methyl-2-pyrrolidone, 1-ethyl-2-pyrrolidone, 1,5-dimethyl-pyrrolidone and 5-methyl-2-pyrrolidone), multilamellar liposome was prepared from the simulated stratum corneum lipid and employed as a model system for the barrier function of the stratum corneum. The liposomal membrane of the stratum corneum lipid liposome (SCLL) behaves as an osmometer and has an excellent barrier function. In addition, its phase transition temperatures are similar to those of human stratum corneum intercellular lipid region. Therefore, SCLL seems to be a useful skin model. To estimate the barrier function of SCLL, the osmotic behavior of SCLL was measured in the presence of pyrrolidone derivatives and the effect on the phase transition temperature of SCLL was also investigated using differential calorimetry. Above a certain concentration (MLAC), enhances perturb the barrier function of the liposome. The relationship between MLACs and the partition coefficient of the pyrrolidone derivatives was observed; the greater the partition coefficients, the smaller the MLAC. This suggests that the more hydrophobic enhancers penetrate into the lipid layer more easily and reduce the barrier function of membrane more effectively. The results of differential scanning thermograms of the SCLL suggest that the pyrrolidone derivatives had incorporated into the lipid layer in the liposome and increased the fluidity of the lipid layer in the liposome. Such activity might have some correlation with the transdermal absorption-enhancing activity these compounds.

• Korean Journal of Biological Psychiatry
• /
• v.5 no.2
• /
• pp.235-242
• /
• 1998

Objectives : Alcohol-induced oxidative stress has been known to injure various tissues or organs. This stress is related with free radicals which are produced as the result of long-term alcohol consumption. Malonyldialdehyde(MDA) is produced by the interaction of free radicals and cell membrane lipids, and indicates the degree of lipid peroxidation indirectly. The purpose of this study was to investigate the relationship between red blood cell(RBC) membrane lipid peroxidation by free radicals, and associated hepatic injuries and hematologic changes. Methods : Thirty-three subjects diagnosed as alcohol dependence according to DSM-IV diagnostic criteria were evaluated within 72 hours after discontinuing alcohol drinking. Clinical characteristics were evaluated by CAGE questionnaire and Korean Michigan Alcoholism Screening Test(MAST). RBC membrane MDA level was measured as the marker of RBC membrane lipid peroxidation. Aspartate aminotransferase(AST), alanine aminotransferase(ALT) and gamma-glutamyltransferase(GGT) were used as the biochemical markers of liver damage due to alcohol ingestion. The alcohol-induced hematologic change was assessed by mean corpuscular volume(MCV). Results : The results were as follows. Clinical characteristics were not different between two groups having normal and abnormal levels of AST, ALT, GGT or MCV. The levels of MDA were not correlated with the clinical characteristics and serum levels of AST, ALT and GGT. However, there was a significant correlation between the levels of MDA and the value of MCV(p=0.017). Conclusions : These findings suggest that oxidative stress in alcohol dependence may not be reflected in liver enzyme markers such as AST, ALT and GGT, but may be reflected in MCV.

• Bulletin of the Korean Chemical Society
• /
• v.34 no.3
• /
• pp.931-935
• /
• 2013

Lipid events in liposome-mediated transfection (lipofection) are largely unknown. Here we studied whether phospholipase D (PLD), an important enzyme responsible for phospholipid breakdown, was affected during lipofection of HepG2 cells with a luciferase plasmid. Synthetic cholesterol (Chol) derivatives, including $3{\beta}$[L-ornithinamide-carbamoyl]Chol, [polyamidoamine-carbamoyl]Chol and $3{\beta}$[N-(N',N'-dimethylaminoethane)-carbamoyl]Chol, and a cationic lipid, N-[1-(2,3-dioleyloxy)propyl]-N,N,N-trimethylammonium chloride were mixed with a helper lipid dioleoylphosphatidylethanolamine to form respective cationic liposomes. All cationic liposomes were found to stimulate PLD. Although orders of magnitude effects of the cationic liposomes on PLD stimulation did not consistently match those on cytotoxicity and luciferase expression, a causal relationship between PLD activation and cytotoxic effect was remarkable. PLD stimulation by the cationic liposomes was likely due to their amphiphilic characters, leading to membrane perturbation, as supported by similar results obtained with other membrane-perturbing chemicals such as oleate, melittin, and digitonin. Our results suggest that lipofection induces cellular lipid changes such as a PLD-driven phospholipid turnover.

• Journal of Photoscience
• /
• v.8 no.3_4
• /
• pp.123-126
• /
• 2001

We have attempted to determine the Germanium ion (G $e^{4+}$) effect on the human body by observing the formation of artificial lipid membrane and photolysis in the mineral water containing G $e^{4+}$ ion. The artificial lipid membrane is prepared by using the phospholipid in the Germanium water and the formation efficiency of the liposomes is compared with those obtained in the plain mineral water without G $e^{4+}$ ion. This work shows that the liposomes are formed in the Germanium water better than in the non-Germanium water. The liposomes can be photolyzed by superoxide anion ( $O_{2-}$$^{.}$) produced in the presence of some peptide such as NAT (N-acethyl-L-tryptophan). However, this is inhibited by superoxide dismutase (SOD), and it was found that the activity of SOD on the inhibition of the liposomes oxidative damage is higher in the Germanium water than in the non-Germanium water. It is concluded that the G $e^{4+}$ ion in mineral water helps the formation of new cell as well as elevation of SOD activity for the lipid oxidation.n.

• Journal of Photoscience
• /
• v.4 no.3
• /
• pp.133-140
• /
• 1997

A system for studying oxidative hemolysis has been used by controling UV-irradiation and concentration of a novel molecular probe, N,N'-bis(2-hydroperoxy-2-methoxyethyl)-1,4,5,8-naphthalenetetra-carboxylic diimide (NP-III), which generates hydroxyl radical upon longer wavelength photoirradiation (> 350 nm). NP-III induces 25~30% of hemolysis at low concentration (50 $\mu$M) for 3h-irradiation of UVA. The simultaneous treatment of N-ethylmaleimide (NEM) with NP-IH completely hemotyzed erythrocytes under the same conditions as NP-III alone by both decreasing thiol group and increasing lipid peroxidation in erythrocyte membrane. However. thiol-reducing agents prevented the protein-crosslinking and lipid peroxidation on the NEM-synergistic hemolysis by partially scavenging hydroxyl radical and maintaining the thiol group of erythrocyte membrane in the reduced state. In addition, erythrocytes pretreated with 2,2,5,7,8-pentamethyl-6-hydroxychromane (PMC), vitamin E homologue was able to delay and decrease the lipid peroxidation when compared to cells pretreated with both NEM and PMC. We suggest that the presence of reduced thiols in inner membrane protein by GSH can prevent the protein-crosslinking and the lipid peroxidation, and eventually prevent the oxidative hemolysis of erythrocyte.

• Journal of Food Hygiene and Safety
• /
• v.14 no.1
• /
• pp.60-66
• /
• 1999

Diethylnitrosamine (DEN) is known as a potential hepatic carcinogen by single administration. This study was designed to measure the effects of DEN-induced cell damage on the triglyceride and cholesterol concentration in the liver, excluding dietary effects. Fertilized chicken eggs, 10 days before hatching, were randomly divided into three groups (n=20) and each egg was injected 10 ${mu}ell$ of corn oil (vehicle control), 5 $\mu\textrm{g}$ of DEN/10 ${mu}ell$ of DEN/10 ${mu}ell$ into yolk via air sac. After 48 hr and 96 hr incubation, the damage of the chick-embryo liver cell was investigated by electron microscopy and by measuring the concentration of lipid components (total cholesterol, free cholesterol, phospholipid and triglyceride). For eggs administered 10 $\mu\textrm{g}$ of DEN and incuvated 96 hr, in hepatocyte, the nucleus membrane was roughed, the size of nucleolus was apparently increased and euchromatin was accumulated. Mitochondria were condensed and cristae, located mitochondiral inner membrane, were obscured. Additionally, the leaves of triglyceride and cholesterol classes were significantly increased depend on the amount treated with 10 $\mu\textrm{g}$ DEN at 96 hr, but phospholipids component of cell membrane, were decreased with significance. As a conclusion, carcinogen induced hepatic lesion was correlated with the changes in lipid component of liver.

• Korean Chemical Engineering Research
• /
• v.48 no.1
• /
• pp.33-38
• /
• 2010

A microfluidic system has been developed using biomaterial for the measurement of cupric ion concentration. The cell-membrane-mimicking bilayer lipid membrane(BLM)-coated silver electrode was used for the sensing of cupric ion concentration. The silver-supported BLM could increase its stability. A silver-supported bilayer lipid membrane(s-BLM) was easily obtained using its self-assembling characteristics by immersing silver wire into lipid(phosphatidylcholine; PC) solution and then dipping into aqueous KCl solution. These s-BLMs were used to determine the relationship between $Cu^{2+}$ concentration and current crossing s-BLM. Their relationship showed high linearity and reproducibility. The calibration curve was constructed to express the relationship between $Cu^{2+}$ concentration and current in the $Cu^{2+}$ concentration range of 10 and $130{\mu}M$. This calibration curve was used to measure $Cu^{2+}$ concentration in an unknown sample. Microfluidic system with s-BLM was made of PDMS(polydimethyl siloxane) using typical soft photolithography and molding technique. This integrated system has various functions such as activation of the silver surface without cutting silver wire, coating of BLM on silver surface, injection of KCl buffer solution, injection of $Cu^{2+}$ sample and measurement of $Cu^{2+}$ concentration in the sample.

• YAKHAK HOEJI
• /
• v.33 no.1
• /
• pp.15-19
• /
• 1989

The effects of Gypsophila saponin, sodium dodecylsulfate (SDS) and Triton X-100 on volume changes and fragility of red blood cells were compared to ginseng saponin to elucidate whether there are any difference in their action on membrane lipid. Cell volume was decreased to about 38% in 1M NaCl and increased to about 20% in 1/10M NaCl. Hematocrit value was decreased by Gypsophila saponin, SDS, and Triton X-100 which caused hemolysis in isotonic NaCl solution. These detergents also inhibited increase of cell volume and accelerated hemolysis in hypotonic solution. However, ginseng saponin did not influence to osmotic volume changes and hemolysis of red blood cells. These results suggest that the disruptive effect of plant saponin on membrane barriers induced by removing membrane lipid is different from their source and ginseng saponin has very low affinity to membrane lipid.

• Archives of Pharmacal Research
• /
• v.13 no.2
• /
• pp.192-197
• /
• 1990

The microviscosites of the lipid bilayers of liposomal membranes of phospholipids were measured by the intermolecular excimer, formation method employing pyrene as a fluorescence probe, and the effects of n-alkanols and other local anesthetics on the microviscosity were investigated. The results showed that the n-alkanols and the ohter local anesthetics effectively lowered the microviscosity of the lipid bilayer of the dipalmitoyl phosphatidycholine liposomal membrane in proportion to the concentration of the additives. Moreover, there was a fairly good correlation between the ocal anesthetic activities and the microviscosity-lowering activities of these drugs. This results suggests that the nerve blocking activity of local anesthetics might have some relation with their activity fluidizing the lipid bilayer of biomembrane.

• Food Science of Animal Resources
• /
• v.31 no.1
• /
• pp.1-8
• /
• 2011

A unique biophysical membrane which surrounds the milk fat globules is called the milk fat globule membrane (MFGM). Various researches were studied about origin, composition, structure and bioactive components of MFGM. Bioactive protein components of MFGM play an important beneficiary function such as defense mechanism in new born. Among the bioactive lipid components from MFGM phospholipids showed health enhancing functions. The phospholipids also help in the production of certain dairy product from deterioration. MFGM phospholipids also showed antioxidant activity in some dairy products such as butter and ghee produced from milk of buffalo. Based on the beneficial effects, researchers developed MFGM as functional ingredients in various food products. This current review focuses on health enhancing function of MFGM and its components in various dairy products.