Membrane properties of hydroxycholesterols related to the brain cholesterol metabolism

Compared to cholesterol, hydroxycholesterols contain an additional hydroxy group in the alkyl chain and are able to efficiently cross the brain–blood barrier. Therefore, they are responsible for the sterol transfer between brain and circulation. The current study compares the membrane properties of several hydroxycholesterols with those of cholesterol using 2H NMR spectroscopy, a membrane permeability assay, and fluorescence microscopy experiments. It is shown that hydroxycholesterols do not exert the unique impact on membrane properties characteristic for cholesterol with regard to the influence on lipid chain order, membrane permeability and formation of lateral domains.

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Conformational study on ribonucleoside O-phosphonylmethyl derivatives by 1H NMR spectroscopy

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19851899 ◽

1985 ◽

Vol 50 (8) ◽

pp. 1899-1905 ◽

Cited By ~ 4

Author(s):

Milena Masojídková ◽

Jaroslav Zajíček ◽

Miloš Buděšínský ◽

Ivan Rosenberg ◽

Antonín Holý

Keyword(s):

Nmr Spectroscopy ◽

1H Nmr ◽

1H Nmr Spectroscopy ◽

Conformational Study ◽

H Nmr ◽

Conformational Properties

Conformational properties of ribonucleoside 5'-O-phosphonylmethyl derivatives have been determined by 1H NMR spectroscopy and compared with those of natural nucleosides and 5'-nucleotides.

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Monitoring the encapsulation of chlorin e6 derivatives into polymer carriers by NMR spectroscopy

Journal of Porphyrins and Phthalocyanines ◽

10.1142/s1088424619501815 ◽

2019 ◽

Vol 23 (11n12) ◽

pp. 1576-1586 ◽

Cited By ~ 1

Author(s):

Sara Pfister ◽

Luca Sauser ◽

Ilche Gjuroski ◽

Julien Furrer ◽

Martina Vermathen

Keyword(s):

Relaxation Time ◽

Nmr Spectroscopy ◽

Core Region ◽

Chlorin E6 ◽

Polypropylene Glycol ◽

Polymer Carriers ◽

H Nmr ◽

Line Shape Analysis ◽

Dynamic Methods ◽

Derivatives Of

The encapsulation of five derivatives of chlorin e6 with different hydrophobicity and aggregation properties into a series of five poloxamer-type triblock copolymer micelles (BCMs) with varying numbers of polyethylene and polypropylene glycol (PEG, PPG) units was monitored using 1H NMR spectroscopy. NMR chemical shift and line shape analysis, as well as dynamic methods including diffusion ordered spectroscopy (DOSY) and T1 and T2 relaxation time measurements of the chlorin and the polymer resonances, proved useful to assess the chlorin–BCM compatibility. The poloxamers had high capability to break up aggregates formed by chlorins up to intermediate hydrophobicity. Physically entrapped chlorins were always localized in the BCM core region. The loading capacity correlated with chlorin polarity for all poloxamers among which those with the lowest number of PPG units were most efficient. DOSY data revealed that relatively weakly aggregating chlorins partition between the aqueous bulk and micellar environment whereas more hydrophobic chlorins are well retained in the BCM core region, rendering these systems more stable. T1 and T2 relaxation time measurements indicated that motional freedom in the BCM core region contributes to encapsulation efficiency. The BCM corona dynamics were rather insensitive towards chlorin entrapment except for the poloxamers with short PEG chains. The presented data demonstrate that 1H NMR spectroscopy is a powerful complementary tool for probing the compatibility of porphyrinic compounds with polymeric carriers such as poloxamer BCMs, which is a prerequisite in the development of stable and highly efficient drug delivery systems suitable for medical applications like photodynamic therapy of tumors.

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Different submicellar solubilization mechanisms revealed by 1H NMR and 2D diffusion ordered spectroscopy (DOSY)

Physical Chemistry Chemical Physics ◽

10.1039/d0cp00429d ◽

2020 ◽

Vol 22 (19) ◽

pp. 11075-11085

Author(s):

Mengjian Wu ◽

Zhaoxia Wu ◽

Shangwu Ding ◽

Zhong Chen ◽

Xiaohong Cui

Keyword(s):

Nmr Spectroscopy ◽

Sodium Dodecyl Sulfate ◽

1H Nmr ◽

Sodium Dodecyl ◽

Butyl Methacrylate ◽

H Nmr ◽

Molecular Scale ◽

Two Systems ◽

Dodecyl Sulfate ◽

Triton X

Different submicellar solubilization mechanisms of two systems, Triton X-100/tetradecane and sodium dodecyl sulfate (SDS)/butyl methacrylate, are revealed on the molecular scale by 1H NMR spectroscopy and 2D diffusion ordered spectroscopy (DOSY).

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Lipid chain order in Acholeplasma laidlawii membranes

FEBS Letters ◽

10.1016/0014-5793(80)81298-1 ◽

1980 ◽

Vol 109 (1) ◽

pp. 5-8 ◽

Cited By ~ 9

Author(s):

David A. Pink ◽

Martin J. Zuckermann

Keyword(s):

Acholeplasma Laidlawii ◽

Chain Order ◽

Lipid Chain

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Tautomerisation in 1-(4-Methylphenylazo)naphthalen-2-ol and 2-(4-Methylphenylazo)-4-methylphenol: A Crystallographic and 13C{1H}NMR Study

Journal of Chemical Research ◽

10.1177/174751989902300304 ◽

1999 ◽

Vol 23 (3) ◽

pp. 178-179

Author(s):

Wendy I. Cross ◽

Kevin R. Flower ◽

Robin G. Pritchard

Keyword(s):

Acetic Acid ◽

Nmr Spectroscopy ◽

Resonant Frequency ◽

X Ray Diffraction ◽

X Ray ◽

H Nmr ◽

Nmr Study ◽

Acetic Acid Esters ◽

Acid Esters ◽

Equivalent Carbon

The acetic acid esters of 1-(4-methylphenylazo)naphthalen-2-ol 1 and 2-(4-methylphenylazo)-4-methylphenol 3 are prepared and characterised by single crystal X-ray diffraction studies and 13C{1H}NMR spectroscopy; the position of the C(2)13C resonance for the ester is used to predict the position of resonant frequency of the equivalent carbon in the parent alcohols and hence, calculate the position of the azo-hydrazone equilibrium in these compounds.

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3-Hydroxy Retinal, a New Chromophore Identified in Insect Eyes: HPLC Separation and NMR Spectroscopic Identification of the Oxime Forms

Zeitschrift für Naturforschung C ◽

10.1515/znc-1988-5-626 ◽

1988 ◽

Vol 43 (5-6) ◽

pp. 473-475 ◽

Cited By ~ 2

Author(s):

Wolfgang Gärtner ◽

Anette Plangger

Keyword(s):

Nmr Spectroscopy ◽

Separation System ◽

Hplc Separation ◽

H Nmr ◽

Spectroscopic Identification

3-Hydroxy retinal acts as visual chromophore instead of retinal in the eyes of several insect orders. A HPLC separation system of the aldehyde and oxime isomers and their identification by 400 MHz 1H NMR spectroscopy is described.

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Resilience, plasticity and robustness in gene expression during aging in the brain of outbred deer mice

BMC Genomics ◽

10.1186/s12864-021-07613-2 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

E Soltanmohammadi ◽

Y Zhang ◽

I Chatzistamou ◽

H. Kiaris

Keyword(s):

Gene Expression ◽

Cholesterol Metabolism ◽

Expression Profiles ◽

Deer Mice ◽

Abrupt Changes ◽

Transcriptional Changes ◽

Thrombospondin 4 ◽

Whole Transcriptome ◽

The Brain ◽

Shed Light

Abstract Background Genes that belong to the same network are frequently co-expressed, but collectively, how the coordination of the whole transcriptome is perturbed during aging remains unclear. To explore this, we calculated the correlation of each gene in the transcriptome with every other, in the brain of young and older outbred deer mice (P. leucopus and P. maniculatus). Results In about 25 % of the genes, coordination was inversed during aging. Gene Ontology analysis in both species, for the genes that exhibited inverse transcriptomic coordination during aging pointed to alterations in the perception of smell, a known impairment occurring during aging. In P. leucopus, alterations in genes related to cholesterol metabolism were also identified. Among the genes that exhibited the most pronounced inversion in their coordination profiles during aging was THBS4, that encodes for thrombospondin-4, a protein that was recently identified as rejuvenation factor in mice. Relatively to its breadth, abolishment of coordination was more prominent in the long-living P. leucopus than in P. maniculatus but in the latter, the intensity of de-coordination was higher. Conclusions There sults suggest that aging is associated with more stringent retention of expression profiles for some genes and more abrupt changes in others, while more subtle but widespread changes in gene expression appear protective. Our findings shed light in the mode of the transcriptional changes occurring in the brain during aging and suggest that strategies aiming to broader but more modest changes in gene expression may be preferrable to correct aging-associated deregulation in gene expression.

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Water-soluble β-aminobisulfonate building blocks for pH and Cu2+ indicators

RSC Advances ◽

10.1039/c6ra17791c ◽

2016 ◽

Vol 6 (88) ◽

pp. 84712-84721 ◽

Cited By ~ 5

Author(s):

Maria A. Cardona ◽

Marina Kveder ◽

Ulrich Baisch ◽

Michael R. Probert ◽

David C. Magri

Keyword(s):

Nmr Spectroscopy ◽

Building Blocks ◽

Water Soluble ◽

Visible Absorption ◽

H Nmr ◽

Uv Visible

Two phenyl β-aminobisulfonate ligands characterised by UV-visible absorption, EPR and 1H NMR spectroscopy exhibit evidence for binding with Cu2+ in water and methanol.

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