scholarly journals Morphologies and Structure of Brain Lipid Membrane Dispersions

2021 ◽  
Vol 9 ◽  
Author(s):  
Viveka Alfredsson ◽  
Pierandrea Lo Nostro ◽  
Barry Ninham ◽  
Tommy Nylander
Keyword(s):  
Lipid Content ◽  
Salt Solution ◽  
Lipid Membrane ◽  
Structural Parameters ◽  
Cholesterol Content ◽  
Lamellar Phase ◽  
Brain Lipid ◽  
Solution Composition ◽  
Brain Lipids ◽  
Multilamellar Vesicles

This study aims to explore the variety of previously unknown morphologies that brain lipids form in aqueous solutions. We study how these structures are dependent on cholesterol content, salt solution composition, and temperature. For this purpose, dispersions of porcine sphingomyelin with varying amounts of cholesterol as well as dispersions of porcine brain lipid extracts were investigated. We used cryo-TEM to investigate the dispersions at high-salt solution content together with small-angle (SAXD) and wide-angle X-ray diffraction (WAXD) and differential scanning calorimetry (DSC) for dispersions in the corresponding salt solution at high lipid content. Sphingomyelin forms multilamellar vesicles in large excess of aqueous salt solution. These vesicles appear as double rippled bilayers in the images and as split Bragg peaks in SAXD together with a very distinct lamellar phase pattern. These features disappear with increasing temperature, and addition of cholesterol as the WAXD data shows that the peak corresponding to the chain crystallinity disappears. The dispersions of sphingomyelin at high cholesterol content form large vesicular type of structures with smooth bilayers. The repeat distance of the lamellar phase depends on temperature, salt solution composition, and slightly with cholesterol content. The brain lipid extracts form large multilamellar vesicles often attached to assemblies of higher electron density. We think that this is probably an example of supra self-assembly with a multiple-layered vesicle surrounding an interior cubic microphase. This is challenging to resolve. DSC shows the presence of different kinds of water bound to the lipid aggregates as a function of the lipid content. Comparison with the effect of lithium, sodium, and calcium salts on the structural parameters of the sphingomyelin and the morphologies of brain lipid extract morphologies demonstrate that lithium has remarkable effects also at low content.

scholarly journals THE ACTION OF FORMALDEHYDE ON RAT BRAIN LIPIDS

1962 ◽  
Vol 10 (1) ◽  
pp. 79-82 ◽  
Author(s):  
F. A. DEIERKAUF ◽  
F. J. M. HESLINGA
Keyword(s):  
Fatty Acids ◽  
Quantitative Analysis ◽  
Rat Brain ◽  
Paper Chromatography ◽  
Lipid Content ◽  
Cholesterol Esters ◽  
Formaldehyde Solution ◽  
Brain Lipid ◽  
Brain Lipids ◽  
Marked Diminution

The influence of formaldehyde on rat brain lipid was investigated by comparing the analysis of lipids from fresh rat brain with the analysis from rat brains fixed for 110 days in a formaldehyde solution. A quantitative analysis of the lipids using column and paper chromatography is described. Sphingomyclin, cerebrosides and sulphatides were not attacked. Only a slight diminution of phosphatidylserine was indicated. Phosphoinositides remain fairly constant. Of lecithin about 25% was converted to lyso-lecithin. The phosphatidylethanolamine and lyso-phosphatidylethanolamine fractions suffered a marked diminution and the reaction with formaldehyde was noticeable in a change of chromatographic behaviour. The fraction containing cholesterol, cholesterol esters, glycerides, and fatty acids increased, the increase being correlated with the decrease of other fractions by the formation of lyso compounds. After storing tissues for months in formaldehyde solutions a reliable analysis of the lipid content is still possible.

Effect of lipid content of diet on cholesterol content and cholesterogenic enzymes of European eel liver

Lipids ◽  
1993 ◽  
Vol 28 (10) ◽  
pp. 913-916 ◽  
Author(s):  
C. Burgos ◽  
M. F. Zafra ◽  
M. Castillo ◽  
E. Garcia-Peregrin
Keyword(s):  
Lipid Content ◽  
Cholesterol Content ◽  
European Eel

Abstract 631: Lipid Composition of Gold Nanoparticle-Templated High-Density Lipoprotein Analogs Dictates Cholesterol Efflux Function

2014 ◽  
Vol 34 (suppl_1) ◽  
Author(s):  
R Kannan Mutharasan ◽  
Amritha T Singh ◽  
Kaylin M McMahon ◽  
C Shad Thaxton
Keyword(s):  
Fatty Acid ◽  
Lipid Content ◽  
Lipid Composition ◽  
Reverse Cholesterol Transport ◽  
Cholesterol Efflux ◽  
Lipid Membrane ◽  
Density Lipoprotein ◽  
High Density ◽  
High Density Lipoproteins ◽  
Cholesterol Transport

Background: Reverse cholesterol transport, the process by which cholesterol is effluxed from cells to high-density lipoproteins (HDL) and is delivered to the liver for clearance, is a promising pathway to augment for treatment of atherosclerosis. Though structure-function relationships for nascent, discoidal HDL and cholesterol efflux have been well studied, how the lipid composition of spherical HDL species - which varies in pathophysiological conditions - impacts their ability to mediate cholesterol efflux has not been investigated. Methods and Results: Spherical gold nanoparticles (5 nm) were used to synthesize spherical HDL analogs (HDL-NP) by adding ApoAI protein, and various lipids. With this strategy a panel of HDL-NP varying in lipid content was generated. HDL-NP designs tested include: dipalmitylphosphatidylcholine (DPPC, saturated fatty acid), dioleoylphosphatidylcholine (DOPC, unsaturated fatty acid), sphingomyelin, lysophosphatidylcholine (LPC), and mixtures thereof. All of these species are found in natural HDL. After characterizing protein and lipid stoichiometry of the purified HDL-NP, these HDL-NP designs were tested in the cellular reverse cholesterol transport assay using J774 mouse macrophages. These studies demonstrate that all HDL-NP designs mediate more efflux than equimolar amounts of ApoAI protein control, and further demonstrate that HDL-NP designs incorporating unsaturated phospholipid (DOPC), sphingomyelin, and LPC - each of which can increase disorder in the lipid membrane and thus give rise to opportunity for cholesterol to intercalate and bind - enhance cholesterol efflux compared to saturated phospholipid (DPPC) design. Conclusion: In summary, these results demonstrate that lipid content of HDL-NP - analogs of spherical HDL - dictates cholesterol efflux function, a finding which sheds light on the functional importance of lipid content variation seen in mature, spherical HDL species.

Evaluation of Angus, Charolais, and Hereford as terminal sire breeds on Hereford and first-cross cows. III. Meat quality of progeny

1998 ◽  
Vol 49 (6) ◽  
pp. 1009 ◽  
Author(s):  
H. Hearnshaw ◽  
P. F. Arthur ◽  
W. R. Shorthose ◽  
A. J. Sinclair ◽  
D. Johnston ◽  
...  
Keyword(s):  
Meat Quality ◽  
Lipid Content ◽  
Bos Indicus ◽  
Subcutaneous Fat ◽  
Cholesterol Content ◽  
Peak Force ◽  
Taste Panel ◽  
Overall Acceptability ◽  
Meat Samples ◽  
Sire Breed

Carcasses of 435 Angus, Charolais, and Hereford sired progeny out of straightbred Hereford (H × H), and first-cross Brahman × Hereford (B × H), Simmental × Hereford (S × H) and Friesian × Hereford (F × H) dams, were evaluated for meat quality traits. The cattle had been raised and slaughtered for the vealer (both sexes), yearling domestic (both sexes), or the heavy export steer market. Meat samples from the M. longissimus (LD, striploin) and the M. semitendinosis (ST, eyeround) were evaluated for colour, cooking loss, sarcomere length, shear force parameters, instron compression values, lipid content (LD only), cholesterol content (LD, vealers only), and taste panel assessment (LD only). The effects of sire breed and dam breed were small and were significant for only a few traits. The use of either hot carcass weight or pH of meat as a covariate reduced the differences further but did not change sire breed or dam breed rankings. Meat from B × H progeny, which had 25% Bos indicus (Brahman) breeding, was as tender as that from progeny of the other dam breeds, which had no Bos indicus breeding. Striploins from vealer carcasses were more tender and had less fat (mean peak force, 3·8 kg; mean lipid in lean steak, 3·8 g/100 g) than those from yearling domestic carcasses (mean peak force, 4·1 kg; mean lipid in lean steak, 5· 0 g/100 g) which in turn were more tender than those from heavy export steer carcasses (mean peak force, 4·9 kg; mean lipid in lean steak, 6·3 g/100 g). From the total responses of the taste panel, 65% rated vealer striploins of good or excellent overall acceptability, compared with 29% for heavy export steer meat. Trimming subcutaneous fat from striploin steaks of vealers reduced lipid content and cholesterol content by 85% and 32% to 3·8 g/100 g and 55 mg/100 g, respectively.

scholarly journals Changes in sperm quality and lipid composition during cryopreservation of boar semen

Reproduction ◽  
2001 ◽  
pp. 395-401 ◽  
Author(s):  
S Cerolini ◽  
A Maldjian ◽  
F Pizzi ◽  
TM Gliozzi
Keyword(s):  
Lipid Content ◽  
Free Cholesterol ◽  
Sperm Quality ◽  
Cholesterol Content ◽  
Sperm Viability ◽  
Freezing And Thawing ◽  
Motile Cells ◽  
Boar Semen ◽  
Thawing Procedure ◽  
Fresh Semen

The effect of cryopreservation on boar sperm viability, motility, lipid content and antioxidant enzymatic activities was studied. Three classes of semen were determined according to a cluster analysis on the basis of the proportion of live and dead cells after freezing and thawing. The classes identified were: high (H, n = 4), average (A, n = 12) and low (L, n = 3) viability. The concentration of sperm cells decreased from class H to A to L. Fresh semen samples with higher viability and a higher proportion of motile cells also maintained better quality after the freezing and thawing procedure. Sperm viability and motility in both fresh and thawed samples were similar in classes H and A, while significantly lower values were measured in class L. The relative decrease in sperm viability and motility after cryopreservation increased from class H to A to L. The lipid content of spermatozoa (micrograms per 10(9) cells) increased significantly after freezing and thawing in classes H and A but not in class L. This result indicated that active sperm lipid metabolism might be responsible for the increase in lipid content. Phospholipid and triacylglycerol contents increased whereas free cholesterol content decreased after thawing. The fatty acid composition of fresh spermatozoa was similar in all three classes. The proportion of polyunsaturated fatty acids decreased significantly after freezing and thawing, indicating contamination from the diluent or peroxidation. After freezing and thawing, superoxide dismutase activity in spermatozoa was significantly higher in class L than in classes H and A, which did not differ from each other.

Effect of salt solution composition on moisture release curves of soil

Soil Research ◽  
1979 ◽  
Vol 17 (1) ◽  
pp. 89 ◽  
Author(s):  
NS Jayawardane ◽  
JA Beattie
Keyword(s):  
Pore Size ◽  
Salt Solution ◽  
Electrolyte Concentration ◽  
Sodium Absorption ◽  
Alluvial Soils ◽  
Salt Solutions ◽  
Solution Composition ◽  
Sodium Absorption Ratio ◽  
Wide Range ◽  
Size Index

A pore size index was used to express quantitatively the relative decrease in size of common pore of confined columns of krasnozem, red-brown and alluvial soils, with reduction in electrolyte concentration of percolating solutions of a given sodium absorption ratio (SAR). The pore size index of red-brown and alluvial soils decreased markedly with reduction in electrolyte concentration, especially in solutions of high SAR. In the krasnozem soil the pore size index remained fairly constant for a wide range of salt solutions. Moisture release curves of red-brown soil for solutions of decreasing electrolyte concentration and constant SAR and for solutions of increasing SAR and constant electrolyte concentration can be used in combination to obtain moisture release curves of this soil for solutions at any intermediate values of SAR and electrolyte concentration. They also reveal the pattern of volume change of different sized pores.

Cholesterol Content in Meat of Some Poultry and Fish Species As Influenced by Live Weight and Total Lipid Content

2003 ◽  
Vol 51 (26) ◽  
pp. 7692-7697 ◽  
Author(s):  
T. Komprda ◽  
J. Zelenka ◽  
E. Fajmonová ◽  
P. Bakaj ◽  
P. Pechová
Keyword(s):  
Fish Species ◽  
Total Lipid ◽  
Lipid Content ◽  
Live Weight ◽  
Total Lipid Content ◽  
Cholesterol Content

scholarly journals Brain lipids in rats fed a diet supplemented with hen eggs of modified lipid content

2012 ◽  
Vol 62 (5-6) ◽  
pp. 641-652
Author(s):  
Aida Hodzic ◽  
T. Goletic ◽  
M. Hamamdzic ◽  
A. Gagic ◽  
Eva Pasic-Juhas ◽  
...  
Keyword(s):  
Lipid Content ◽  
Brain Lipids

scholarly journals Lipogenesis in the brain of suckling rats. Studies on the mechanism of mitochondrial-cytosolic carbon transfer

1980 ◽  
Vol 188 (1) ◽  
pp. 163-168 ◽  
Author(s):  
Tarun B. Patel ◽  
John B. Clark
Keyword(s):  
Rat Brain ◽  
Mitochondrial Membrane ◽  
Lipid Fraction ◽  
Co2 Production ◽  
Brain Lipid ◽  
Atp Citrate Lyase ◽  
Brain Lipids ◽  
Citrate Lyase ◽  
Carbon Transfer ◽  
The Brain

1. Studies on the incorporation of [3-14C]pyruvate and d-3-hydroxy[3-14C]butyrate into the brain lipid fraction by brain homogenates of the suckling (7-day-old) rat have been carried out. 2. Whereas approximately twice as much CO2 was evolved from pyruvate compared with 3-hydroxybutyrate metabolism, similar amounts of the radioactivity of these two precursors were incorporated into the lipid fraction. Furthermore, in both cases the incorporation into lipid was almost tripled when glucose (10mm) or NADPH (2.5mm) was added to the incubation media. 3. If 5mm-(—)-hydroxycitrate, an ATP–citrate lyase inhibitor, was added to the incubation the incorporation of carbon from pyruvate was inhibited to 39% of the control and from 3-hydroxybutyrate to 73% of the control, whereas CO2 production from both precursors was not affected. 4. The incorporation from pyruvate or 3-hydroxybutyrate into lipids was not affected by the presence of 10mm-glutamate in the medium (to encourage N-acetylaspartate production). However, incorporation from pyruvate was inhibited by 21% in the presence of 5mm-amino-oxyacetate (a transaminase inhibitor) and by 83% in the presence of both hydroxycitrate (5mm) and amino-oxyacetate. 5. Incorporation from 3-hydroxybutyrate into brain lipids was inhibited by 20% by amino-oxyacetate alone, but by 55% in the presence of both hydroxycitrate and amino-oxyacetate. 6. It is concluded that the mechanism of carbon transfer from pyruvate into lipids across the mitochondrial membrane in the suckling rat brain is mainly via citrate and N-acetylaspartate. 3-Hydroxybutyrate, in addition to using these routes, may also be incorporated via acetoacetate formation and transport to the cytosol.

Sign in / Sign up

Export Citation Format

Share Document