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PubMed1981

Organization of membrane lipids and proteins in human En(a-) erythrocytes that lack the major sialoglycoprotein, glycophorin A. A spin-label study.

Membrane fluidity was studied by electron-spin-resonance techniques in human En(a-) erythrocytes that lack the major membrane sialoglycoprotein, glycophorin A. By using stearic acid spin labels with a doxyl group in the C-12 or C-15 positions, we demonstrated that the hydrophobic core in these cells was more fluid than in normal cells. Surface-located regions in isolated En(a-) membranes, when probed with stearic acid labelled in the C-5 position, appeared more stable than in normal membranes. In isolated En(a-) membranes, protein motion was decreased when probed with a nitroxide derivative of maleimide. After incubation with anti-(glycophorin A) antibodies protein motion and membrane fluidity were increased in normal membranes. This effect was observed also after spectrin depletion, which by itself increased protein motion but decreased membrane fluidity in the hydrophobic core of the membrane. The results show that membrane proteins influence the fluidity of membrane lipids.

Blood Group Antigens↗
PubMed1989

Influences of tromantadine and nonoxinol 9 on the stability of red cell membrane.

The antiviral compound tromantadine (ViruMerz) and the detergent nonoxinol 9 have been investigated in their effects on biophysical parameters of red cell membranes. Up to a maximum ratio of 1 mol per 800 mol of phospholipids tromantadine enhances the membrane phase transition/separation break at 16-20 degrees C measured by 1-anilinonaphthalene-sulfonate (ANS) fluorescence. It also increases order parameters obtained from spin labeling experiments with 5-doxyl stearic acid. Nonoxinol 9 interacts with the membrane at a maximum ratio of 1 mol per 40 mol of phospholipids determined by UV spectrophotometry. The substance decreases the intensity of the above phase transition/separation break and the order parameters of the spin label 5-doxyl stearic acid. These experiments indicate that tromantadine probably stabilizes the membrane whereas nonoxynol 9 exhibits opposite effects. Combination of both compounds equalizes the influences of the single substances on the above biophysical parameters of red cell membrane with predominance of the nonoxinol 9 effect.

Amantadine↗
PubMed2002

Synthesis of a novel phosphatidylcholine conjugated to docosahexaenoic acid and methotrexate that inhibits cell proliferation.

Here we report the synthesis and characterization of a lipophilic phosphatidylcholine containing the omega-3 fatty acid docosahexaenoic acid (DHA) and the cytotoxic drug methotrexate (MTX). This novel phospholipid combines the fatty acid's and the drug's anticancer activities in a molecule amenable to a liposome bilayer for safe, simultaneous delivery of the two agents. Two phosphatidylcholines were synthesized, from 1-stearoyl or 1-docosahexaenoyl, 2-hydroxy-sn-glycero-3-phosphocholine, to contain MTX in the sn-2 position and either stearic acid or DHA in the sn-1 position. The products contain fatty acid, MTX and phosphorus (1:1:1), and the MTX was released by phospholipase A(2), consistent with the proposed phospholipid structure. The predominant product linked MTX to the glycerol moiety through MTX's gamma-carboxyl group. Liposomes composed of 1-stearoyl, 2-oleoyl phosphatidylcholine plus 1-stearoyl, 2-oleoyl phosphatidylethanolamine and various concentrations of the novel phospholipids caused dose-dependent inhibition of murine leukemia cell proliferation in culture. The DHA- and MTX-containing phosphatidylcholine was more effective than that containing stearic acid, and DHA appeared to synergize with MTX when they were added as free agents or covalently linked in the phospholipid. These data show the feasibility of synthesizing, and the inhibitory activity of phosphatidylcholine with DHA in the sn-1 position and MTX in the sn-2 position, and suggest the compound's potential use in cancer chemotherapy.

Animals↗
PubMed2002

Upstream of growth and differentiation factor 1 (uog1), a mammalian homolog of the yeast longevity assurance gene 1 (LAG1), regulates N-stearoyl-sphinganine (C18-(dihydro)ceramide) synthesis in a fumonisin B1-independent manner in mammalian cells.

The longevity assurance gene (LAG1) and its homolog (LAC1) are required for acyl-CoA-dependent synthesis of ceramides containing very long acyl chain (e.g. C26) fatty acids in yeast, and a homolog of LAG1, ASC1, confers resistance in plants to fumonisin B(1), an inhibitor of ceramide synthesis. To understand further the mechanism of regulation of ceramide synthesis, we now characterize a mammalian homolog of LAG1, upstream of growth and differentiation factor-1 (uog1). cDNA clones of uog1 were obtained from expression sequence-tagged clones and sub-cloned into a mammalian expression vector. Transient transfection of human embryonic kidney 293T cells with uog1 followed by metabolic labeling with [4,5-(3)H]sphinganine or L-3-[(3)H]serine demonstrated that uog1 conferred fumonisin B(1) resistance with respect to the ability of the cells to continue to produce ceramide. Surprisingly, this ceramide was channeled into neutral glycosphingolipids but not into gangliosides. Electrospray tandem mass spectrometry confirmed the elevation in sphingolipids and revealed that the ceramides and neutral glycosphingolipids of uog1-transfected cells contain primarily stearic acid (C18), that this enrichment was further increased by FB(1), and that the amount of stearic acid in sphingomyelin was also increased. UOG1 was localized to the endoplasmic reticulum, demonstrating that the fatty acid selectivity and the fumonisin B(1) resistance are not due to a subcellular localization different from that found previously for ceramide synthase activity. Furthermore, in vitro assays of uog1-transfected cells demonstrated elevated ceramide synthase activity when stearoyl-CoA but not palmitoyl-CoA was used as substrate. We propose a role for UOG1 in regulating C18-ceramide (N-stearoyl-sphinganine) synthesis, and we note that not only is this the first case of ceramide formation in mammalian cells with such a high degree of fatty acid specificity, but also that the N-stearoyl-sphinganine produced by UOG1 most significantly impacts neutral glycosphingolipid synthesis.

Animals↗
PubMed1982

Changes in hepatic microsomal membrane fluidity with age.

There are changes in the mixed function oxidase enzymatic activities of rat hepatic microsomal membranes with age. However, the protein components of the mixed function oxidase system do not appear to change with age. The purpose of this study was to detect possible changes in the fluidity of the lipid component of the microsomal membrane with age. Hepatic microsomes were isolated by differential centrifugation from uninduced, male CFN rats aged 3, 12 and 26 mo. The microsomal membrane fluidity was measured using electron paramagnetic resonance after incorporation of a 5-nitroxide stearic acid spin label into the membrane. The order parameter S decreased with age from 0.586 +/- 0.003 (3 mo) to 0.581 +/- 0.002 (12 mo) to 0.569 +/- 0.003 (26 mo) at 30 degrees C. This indicated an increase in membrane fluidity with age. In membranes labeled with the 16-nitroxide stearic acid, a similar increase in membrane fluidity with age was observed. The order parameter of microsomal membranes from 3 and 26 mo rats was measured over the temperature range 10 degrees to 31 degrees C in steps of 0.9 degrees C. A plot of the log of S versus the reciprocal temperature revealed a phase transition at 24 degrees C in membranes from 26 mo rats, but no phase transition was observed in 3 mo old rats in this temperature range. The change in fluidity of the hepatic microsomal membrane with age may account for some of the observed changes in membrane-bound mixed function oxidase activities with age.

Aging↗
PubMed1985

Kinetics of different 123I- and 14C-labelled fatty acids in normal and diabetic rat myocardium in vivo.

Terminally radioiodinated long-chain fatty acids (FA) or phenyl-FA have shown promise for external myocardial imaging and detection of metabolic disorders with changes like those seen with radiocarbon-labelled natural FA. Yet, questions remain about the correlation of these changes to the biochemical forms of radioiodine within the cell. We have measured the distribution of label from 123I-heptadecanoic acid (HA), 123I-para-phenyl- and ortho-phenylpentadecanoic acid (pPPA and oPPA), 1-14C-stearic acid (SA) and 1-14C-palmitic acid (PA) into complex lipids (CL) (i.e. triacylglycerols (TG) and phospholipids (PL)), aqueous phase (AP) and solid residue (SR) of myocardium of normal (N) and streptozotocin-diabetic (D) rats at 1,2, 3, 5 and 10 min after i.v. injection. For the total heart (TH) all FA have similar initial peak heights in % dose (pPPA highest) at 1 to 2 min in N and D. Tracer kinetics for CL, TG and PL were similar for PA and pPPA and for SA and HA. For PA and pPPA 2/3 of CL tracer were in TG and 1/3 in PL, whereas it was 1/2 in each for SA and HA. In D rats turnover of CL was enhanced and tracer uptake into TG reduced for all FA. Tracer kinetics in SR and AP were similar, with highest values for HA; relationship between peak times for CL and AP indicates rapid formation of catabolite and its early cell exit. Unlike pPPA, oPPA was little converted to TG or PL and equally in N and D rats showed rapid decline.

Animals↗
PubMedDate not supplied

Development and evaluation of controlled-release diclofenac microspheres and tabletted microspheres.

Diclofenac wax microspheres were prepared using the congealable dispersephase encapsulation method. Emulsifiers, glyceryl monostearate (GMS) and stearic acid, were added to improve the efficiency of emulsification. Microspheres containing either of the emulsifiers or both showed a high drug content (80-90%) and the particle size distribution was log-normal compared with microspheres without the emulsifiers. Increase in GMS concentration decreased the drug release and, in contrast, stearic acid appeared to channel the drug from the wax matrix. The addition of both emulsifiers at different concentrations modified drug release. Increase in dispersant (PVP) concentration, and decrease in microsphere size accelerated the rate of drug release. Higuchi/Baker Londsdale spherical matrix dissolution kinetics was followed. Disintegrating tableted microspheres were prepared with Avicel and Explotab. With the increase in compression pressure the crushing force and disintegrating time increased, but the thickness decreased, and the dissolution profile did not appear to be affected. Slightly faster release was noticed with tableted microspheres compared with that of uncompressed microspheres. Tablets containing 40 and 60% microsphere loadings had disintegration times of 5.12 +/- 0.63 and 57.73 +/- 3.53 min, respectively. In contrast, tablet formulation containing 80% microsphere load had a significant increase in disintegration time (130.83 +/- 4.26 min). The dissolution from this formulation also showed a lag time of 30 min in contrast with the other two formulations, which showed no lag time. Increased microsphere size from 215 to 630 microns had no effect on tableting properties (such as hardness and thickness); and only very little effect on dissolution. The microspheres appeared deformed but intact irrespective of compression pressures on scanning electron micrographs.

Delayed-Action Preparations↗
PubMed2002

Hydrophobic mechanochemical treatment of metallic surfaces wettability measurements as a means of assessing homogeneity.

Hydrophobicity, lubrication and anticorrosion properties of steel substrates have been obtained by a deposition of thin film (i.e. by mechanochemical treatment) at room conditions. Stearic acid and paraffin were chosen as reactive molecules. Different abrasive powders were selected to generate active sites on the treated surfaces for adsorption of the reactive molecules and then, the results were compared. The surfaces were analyzed by reflection-absorption infrared spectroscopy (RAIRS). The results emphasize that, a thick layer of mixed stearic acid/paraffin was deposited onto the metallic surface after the treatment. After hexane rinsing we could only detect a very thin layer of oriented stearic acid molecules chemically adsorbed onto the metallic surface and which engages strong interactions with it. Whereas, RAIRS only provides molecular analysis, the XPS technique was complementary for discriminating the different surfaces. It was possible to show differences in thickness as well as in coverage according to the size and shape of abrasive particles. Furthermore, we could conclude that deposit layer is not uniform. Defects were always present and were dependent on abrasive powders used. Then wettability was assessed as a way to test the homogeneity of thin films generated by the mechanochemical treatment. In agreement with theoretical data, receding contact angle was very dependent on the defects in the deposited film. If holes or aggregates were increased in the deposit layer, the receding contact angle was decreased while advancing contact angles and equilibrium contact angles remained constant. A very important point for technological applications was that the homogeneity of the deposited film was governed by abrasive powder involved in mechanochemical treatment and contact angle values were a direct measurement of the homogeneity of surfaces generated by mechanochemical treatment.

Journal Article↗
PubMed1996

Interaction of glucose and metformin with isolated red cell membrane.

Isolated human erythrocyte membranes (red blood cell (RBC) ghosts) were incubated with glucose at 5, 10, 20 and 100 mmol/l concentrations, with insulin (0.01 to 200 mU/l) and metformin (CAS 657-24-9) 0.5 up to 50.0 mumol/l). Binding studies with 14C-glucose and subsequent gel electrophoresis revealed 60% of the radioactivity around ban 4.2-4.5 at 5 mmol/l, whereas a random distribution of radioactivity over all protein bands of the RBC membrane was found at 20 mmol/l concentration after incubation for 30 min or 48 h. Metformin does not bind covalently to RBC membranes, however, after photochemical linkage of 14C-metformin via the aminoreactive linker azidophenylglyoxal the highest radioactivity (21%) was counted in the range of band 4.2-4.5. In parallel with an increase of order parameters of 5-doxyl-stearic acid the thiol status of the membranes decreases as determined by monobromobimane fluorescence. 20 and 100 mmol/l concentrations of glucose decrease the reactivity of membrane thiols towards bromobimane significantly to 73 and 62% of the controls. Concomitantly, membrane fluidity at polar sites is diminished as measured by order parameters of spin label 5-doxyl stearic acid. In RBC membranes pretreated with 20 mmol/l glucose the decreased fluorescence is significantly raised again by insulin and metformin. This effect is even more pronounced, if insulin and metformin are incubated together. Reaction of membrane thiols with a maleimido spin label detects modification in the ratio of mobile and immobilized spin label populations in the electron paramagnetic resonance signal under the above conditions, indicative of conformational changes of membrane proteins.

Bridged Bicyclo Compounds↗
PubMed1996

Influences of lipid and non-lipid nutritional parameters on factor VII coagulant activity in normal subjects: the Nove study.

Community-based studies have suggested that the dietary intake of total fat influences factor VII coagulant activity (FVIIc), a predictor of fatal events from coronary heart disease (CHD). Nevertheless, the question whether the quality of dietary fats, with special reference to fatty acids (FAs), influences FVIIc is unsolved. The authors investigated in 90 healthy volunteers living in Nove, a village near Vicenza (northern Italy), the relationships between FVIIc and the plasma concentration of individual FAs. Several indices of other nutritional factors that have recently received increasing attention as determinants of CHD risk (antioxidant vitamins A and E, oligoelements) were also included in the multivariate analysis. The stepwise multiple linear regression analysis revealed body mass index (BMI), and the concentrations of plasma stearic acid (C18:0) and serum copper as significant independent predictors of a substantial proportion of FVIIc variability (R = 0 center dot 52; R2 = 0 center dot 27; P < 0 center dot 001). This study substantially supports the role of the plasma concentration of stearic acid as an important factor in modulating FVIIc.

Adult↗
PubMed2001

Pulmonary surfactant protein SP-B is significantly more immunoreactive in anionic than in zwitterionic bilayers.

Binding of polyclonal and monoclonal antibodies, quantitated by enzyme-linked immunosorbent assay, to porcine SP-B reconstituted in different phospholipid bilayers has been used to assess differences in protein structure due to lipid-protein interactions. SP-B bound significantly more antibodies when it was reconstituted in bilayers made of anionic phospholipids (phosphatidic acid, cardiolipin, phosphatidylglycerol, phosphatidylinositol or phosphatidylserine) than in zwitterionic bilayers (phosphatidylcholine, phosphatidylcholine/cholesterol, or phosphatidylethanolamine) or in fatty acid micelles (made of salts of palmitic or stearic acids). These differences in immunoreactivity can be important in the development of quantitation methods for SP-B in clinical samples based on immunological techniques.

Animals↗
PubMed2005

Effect of metal ions on monolayer collapses.

A Langmuir monolayer of stearic acid on pure water and in the presence of certain divalent metal ions such as Cd and Pb at pH approximately 6.5 of the subphase water collapses at constant area, while for other divalent ions such as Mg, Co, Zn, and Mn at the same subphase pH the monolayer collapses nearly at constant pressure. Films of stearic acid with Cd, Pb, Mn, and Co in the subphase (at pH approximately 6.5) have been transferred onto hydrophilic Si(001) using a horizontal deposition technique, just after and long after collapse. Electron density profiles obtained from X-ray reflectivity analysis show that a three-molecular-layer structure starts to form just after constant area collapse, where in the lowest molecular layer, in contact with the substrate, molecules are in asymmetric configuration, i.e., both hydrocarbon tails are on the same side of the metal-bearing headgroup that touches the substrate, while the molecules above the first layer are in symmetric conformation of the tails with respect to the headgroups. Further along collapse, when the surface pressure starts to rise again with a decrease in area, more layers with molecules in the symmetric configuration are added, but the coverage is poor. On the other hand, only bimolecular layers form after constant pressure collapse, with the lower and upper layers having molecules in asymmetric and symmetric configurations, respectively, and the upper molecular layer density increases with compression of the monolayer after collapse. A "Ries mechanism" for constant area collapse and a "folding and sliding mechanism" for constant pressure collapse have been proposed.

Journal Article↗
PubMed1994

Calcium overload and cardiac myocyte cell damage induced by arachidonate lipoxygenation.

The accumulation of arachidonic acid and lipoxygenase metabolites of arachidonate occurs in ischemic-reperfused myocardium. Although lipoxygenase inhibitors have been shown to attenuate myocardial infarct size after ischemia-reperfusion, the relationship between arachidonate lipoxygenation and myocardial injury remains unclear. To investigate the direct effect of arachidonate lipoxygenation on cardiac myocytes, isolated rat cardiac myocytes loaded with indo 1 were superfused with Tyrode solution containing arachidonic acid mixed with soybean lipoxygenase. Although neither arachidonic acid nor lipoxygenase alone had any effects, arachidonic acid plus lipoxygenase induced an increase in the twitch amplitude associated with an increased intracellular Ca2+ concentration ([Ca2+]i) and irreversible hypercontracture. Nordihydroguaiaretic acid, a lipoxygenase inhibitor, blocked these effects. Linolenic acid, which is also a lipoxygenase substrate, caused the same effects as arachidonic acid in the presence of lipoxygenase, whereas oleic and stearic acid, which do not function as lipoxygenase substrates, did not. Both ascorbic acid and alpha-tocopherol attenuated an increase in [Ca2+]i and the cellular damage, whereas nicardipine and superoxide dismutase had no effects. These results suggest that lipoxygenase metabolites of arachidonic acid cause intracellular Ca2+ overload and cellular damage to cardiomyocytes, probably through augmentation of lipid peroxidation of the cell membranes by free radicals.

Animals↗
PubMed2006

Electron spin resonance spectroscopy of serum albumin: a novel new test for cancer diagnosis and monitoring.

BACKGROUND: Proteins released by tumor cells can bind to serum albumin, leading to structural and functional modifications. We used electron spin resonance (ESR) spectroscopy to measure these changes in serum albumin and evaluate their utility for the diagnosis and monitoring of cancer. METHODS: We used an ESR spectrometer and 16-doxyl stearic acid as spin probe to measure conformational changes in albumin in blood samples from a population of healthy donors and volunteers (n=349), patients with a wide variety of hematologic and nonhematologic malignancy (n=135), and patients with chronic diseases such as gastrointestinal and pulmonary disease, diabetes, and cirrhosis (n=91). We added differing amounts of 16-doxyl stearic acid spin probe in ethanol to 50 microL of serum from each patient to create 3 different aliquots that differed in concentration of spin probe and ethanol, then incubated the aliquots for 10 min at 37 degrees C with continuous shaking. We measured the ESR spectra of each aliquot in triplicate and used proprietary software (MedInnovation GmbH) to evaluate the ESR spectrum for differences between cancer patients and the other groups. RESULTS: The diagnostic sensitivity and specificity of this test were 87.4% and 95.7%, respectively, for differentiating healthy individuals from cancer patients and 87.4%, and 85.7% for differentiating cancer patients from chronic disease patients. Serial evaluation of albumin conformation changes in several patients followed during the course of their disease showed excellent agreement between the magnitude of abnormality in the ESR spectrum of albumin and clinical and pathologic estimates of disease severity. CONCLUSIONS: ESR spectroscopy of serum albumin is a sensitive and noninvasive technique that clearly demonstrates diagnostic utility in patients with cancer. This test also enables monitoring of the disease course through use of serial measurements.

Adolescent↗
PubMed1994

Regulation of cholesterol uptake in the rat intestinal cell line.

A new model to study cholesterol absorption in the rat intestinal cells is described. Rat intestine epithelial cells IRD98 were incubated with mixed micelles containing bile acid, phospholipid, cholesterol or its nonabsorbable analogue, sitosterol, and trace amounts of [3H]cholesterol or [14C]sitosterol. Cholesterol and sitosterol uptake was then determined following lipid extraction; specific cholesterol uptake was determined as the difference between cholesterol and sitosterol uptake. Cholesterol, but not sitosterol, uptake was time- and dose-dependent and saturable. Loading of cells with non-lipoprotein cholesterol reduced cholesterol, but not sitosterol, uptake in a dose-dependent manner. In contrast, treatment of cells with an inhibitor of cholesterol synthesis, lovastatin, stimulated cholesterol, but not sitosterol, uptake in a dose-dependent manner. Treatment of cells with palmitic, caproic and oleic acids up-regulated specific cholesterol uptake, while linoleic and stearic acids had an opposite effect. None of the fatty acids affected sitosterol uptake.

Animals↗
PubMed1984

Isaxonine base is a strong perturber of phospholipid bilayer order and fluidity--a differential scanning calorimetry and spin labeling study.

The effects of the neurotropic drug isaxonine on fully hydrated dipalmitoyl-phosphatidyl-choline (DPPC) bilayers has been studied in the temperature range 0 degree-60 degrees, using differential scanning calorimetry and electron spin resonance spectroscopy, with two stearic acid spin labels. At low concentration (1% mol/mol), isaxonine is trapped in the polar interface and enhances the phospholipid multibilayers organization in the gel state. In contrast, at high concentration (30% mol/mol), the drug disorganizes the phospholipidic structures and may induce domain formation by phase separation. The strong interactions of isaxonine at the lipid-water interface change the ionization state of the stearic acid spin labels which become totally ionized. Then isaxonine acts as a modifier of the surface pH of the bilayer. The strong membrane effects of isaxonine may explain in part its pharmacological properties in vivo.

Calorimetry, Differential Scanning↗
PubMedDate not supplied

[Effect of lipid monolayers on diffusion of oxygen through the air/water interface].

The dependence of the diffusion current on the depth of immersion of the electrode was studied by polarography using an open platinum electrode. As the electrode was brought from the depth of the liquid phase to its surface, an increase in the current under aerobic conditions was observed, due to diffusion of oxygen through the interface. The formation of lipid monolayers of phosphatidylcholine, stearic acid, hexadecanol, octadecanol, eicosanol, and docosanol on the water surface led to a decrease in diffusion current; the effect being most pronounced at a minimal depth of immersion of the electrode. The maximum value of the relative decrease in diffusion current R was obtained for docosanol monolaers. It was shown that the R value increases with increasing surface pressure in monolayers of phosphatidylcholine and stearic acid. It is assumed that the decrease in diffusion flow of O2 in the presence of monolayers is caused by the formation of an energy barrier that prevents the sorption of O2, which is related to the presence of hydrocarbon chains weakly interacting with oxygen.

Air↗
PubMedDate not supplied

Liposomes as cyclosporin A carriers: the influence of ordering of hydrocarbon chains of phosphatidylglycerol liposomes on the association with and topography of cyclosporin A.

The addition of cholesterol and stearylamine to liposomes prepared from phosphatidylglycerol containing saturated and unsaturated fatty acids was studied to determine the effect on binding of cyclosporin A (CsA). It was found that liposomes containing phosphatidylglycerol-stearylamine-cholesterol in the molar ratio of 7:2.25:2 had the highest capacity to bind CsA (36.7 mol of phospholipid to 1 mol of CsA), while binding of CsA to phosphatidylglycerol liposomes, phosphatidylglycerol-stearylamine liposomes, or phosphatidylglycerolcholesterol liposomes was significantly lower (342.9, 174.4 and 422.3 mol of phospholipid to 1 mol of CsA, respectively). The binding of CsA to all these liposomes was compared with their order parameters, obtained by electron spin resonance spectroscopy using 5-nitroxide stearic acid spin probe. It was found that increased binding of CsA paralleled the increased ordering of hydrocarbon chains achieved by addition of cholesterol to these liposomes. When liposomes were prepared from pure dimyristoylphosphatidylglycerol (DMPG), 30.7 mol of DMPG were required to bind 1 mol of CsA. The topography of CsA in phosphatidylglycerol liposomes was established by using 5-nitroxide stearic acid as a spin probe. In DMPG liposomes, CsA was found in hydrocarbon chains adjacent to the polar head group, while in liposomes prepared from phosphatidylglycerol containing mixed fatty acids, CsA was associated with the polar head group region without penetrating the hydrocarbon chains of phosphatidylglycerol.

Cyclosporine↗