1256-86-6Relevant articles and documents
Direct analysis of sterols by derivatization matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and tandem mass spectrometry
Hailat, Iyad,Helleur, Robert J.
, p. 149 - 158 (2014)
RATIONALE Free sterols are neutral molecules that are difficult to analyze by MALDI or ESI and their molecular ions easily fragment. In order to increase their ionization efficiency and selectivity, sterols were derivatized by different reagents. METHODS Selected sterols were converted into their corresponding picolinyl esters, N-methylpyridyl ethers and sulphated esters. The derivatives were optimized for MALDI-TOFMS analysis through proper selection of the matrix. MALDI-TOF/TOF experiments were carried out to study the fragmentation pathways of the derivatives and their use in structural elucidation. Lipid extracts from mussels were used as test samples for MALDI analysis of sterols in biological samples also analyzed by GC/MS for comparison. RESULTS Sterol picolinyl esters were identified as sodiated adducts [M+Na] + and the signal significantly enhanced after addition of sodium acetate (20 mM). Sterol N-methylpyridyl ethers were easily detected as [M] + while sulphated sterols were best detected as [M-H]-. The ester bonds of picolinyl and sulphated esters easily cleaved in MS/MS resulting in diagnostic derivative fragments at m/z 146.03 and 96.89, respectively. Cleavage of the ether bond of N-methylpyridyl ethers gave a diagnostic fragment ion at m/z 110.04. Sterol profiles in mussels obtained by MALDI-TOFMS were in close agreement with those obtained by GC/MS. Two sterols (cholesterol and β-sitosterol) were selected for quantification as their sulphated and picolinyl esters. Calibration curves gave excellent correlation coefficients. CONCLUSIONS Suitable matrices for picolinyl esters are DHB and THAP, for N-methylpyridyl ethers THAP, and for sulphated esters p-nitroaniline and dithranol. Using cholesterol, the limits of detection (LODs) for sulphated esters were 0.2 μg/mL and for picolinyl esters, 1.5 μg/mL. N-Methylpyridyl ethers were found unsuitable for sterol quantitation. Copyright 2013 John Wiley & Sons, Ltd. Copyright
USE OF OXYGENATED CHOLESTEROL SULFATES FOR TREATING AT LEAST ONE OF INSULIN RESISTANCE, DIABETES, AND PREDIABETES
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Page/Page column 34; 35, (2022/01/05)
Aspects of the present disclosure include methods for treating at least one of insulin resistance, diabetes, and prediabetes, and, optionally, also non-alcoholic steatohepatitis (NASH). In practicing the subject methods, an effective amount of at least one compound selected from 25-hydroxycholesterol-3-sulfate (25HC3S), 25- hydroxycholesterol-disulfate (25HCDS), 27-hydroxycholesterol-3-sulfate (27HC3S), 27- hydroxycholesterol-disulfate (27HCDS), 24-hydroxycholesterol-3-sulfate (24HC3S), 24- hydroxycholesterol-disulfate (24HCDS), and 24,25-epoxycholesterol-3-sulfate, or salt thereof is administered to the subject.
NOVEL VASCULAR LEAK INHIBITOR
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Page/Page column 29-30, (2012/09/21)
The present disclosure relates to a novel vascular leakage inhibitor. The novel vascular leakage inhibitor of the present disclosure inhibits the apoptosis of vascular endothelial cells, inhibits the formation of actin stress fibers induced by VEGF, enhances the cortical actin ring structure, and improves the stability of the tight junctions (TJs) between vascular cells, thereby inhibiting vascular leakage. The vascular leakage inhibitor of the present disclosure has the activity of not only reducing vascular permeability but also recovering the integrity of damaged blood vessels. Accordingly, the vascular leakage inhibitor of the present disclosure can prevent or treat various diseases caused by vascular leakage. Since the vascular leakage inhibitor of the present disclosure is synthesized from commercially available or easily synthesizable cholesterols, it has remarkably superior feasibility of commercial synthesis.
