Lysophosphatidylcholine

FIGURE 25.24 Platelet activating factor, formed from Talkyl-2-lysophosphatidylcholine by acetylation at C-2, is degraded by the action of acetylhydrolase. 

Lysolecithin (lysophosphatidylcholine) may be formed by an alternative route that involves lecithin cholesterol acyltransferase (LCAT). This enzyme. 

Sugawara, T. et al., Lysophosphatidylcholine enhances carotenoid uptake from mixed micelles by Caco-2 human intestinal cells, J. Nutr, 131, 2921, 2001. 

FIGURE 12.4 (A) Diagrammatic representation of the separation of major simple lipid classes on silica gel TLC — solvent system hexane diethylether formic acid (80 20 2) (CE = cholesteryl esters, WE = wax esters, HC = hydrocarbon, EEA = free fatty acids, TG = triacylglycerol, CHO = cholesterol, DG = diacylglycerol, PL = phospholipids and other complex lipids). (B) Diagrammatic representation of the separation of major phospholipids on silica gel TLC — solvent sytem chloroform methanol water (70 30 3) (PA = phosphatidic acid, PE = phosphatidylethanolamine, PS = phosphatidylserine, PC = phosphatidylcholine, SPM = sphingomyelin, LPC = Lysophosphatidylcholine). 

Weltzem, H.U. (1979). Cytolytic and membrane-perturbing properties of lysophosphatidylcholine. Biochim. Biophys. Acta 559, 259-287. 

Kume, N., Cybulsky, M.I. and Gimbrone, M.A. (1992). Lysophosphatidylcholine, a component of atherogenic lipoproteins, mediates mononuclear leucocyte adhesion in cultured human and rabbit endothelial cells. J. Clin. Invest. 90, 1138-1144. 

Huang, Y.H., Schafer-Elinder, L., Wu, R., Claesson, H.E., and Frostegard J., 1999b, Lysophosphatidylcholine (LPC) induces proinflammatory cytokines by a plateletactivating factor (PAE) receptor-dependent mechanism, Clin. Exp. Immunol. 116 326-331. 

Paraformaldehyde fixes by crosslinking surface proteins. Ethanol and methanol work through precipitation of membrane components. Triton X-100 and Tween-20 permeabilize membranes. Other permeabilizers are saponin (0.1-10% [v/v] in PBSG), L-lysophosphatidylcholine, and n-octyl-P-D-glucopyranoside (1-10 pg/mL in water). 

This enzyme [EC 2.3.1.23], also called lysolecithin acyl-transferase and lysophosphatidylcholine acyltransferase, catalyzes the reaction of an acyl-CoA derivative with 1-acyl-5 n-glycero-3-phosphocholine to yield coenzyme A and l,2-diacyl-5 n-glycero-3-phosphocholine. The enzyme preferentially acts on unsaturated acyl-CoA derivatives, but l-acyl-5 n-glycero-3-phosphoinositol can also act as the acceptor. 

This enzyme [EC 3.1.1.5] (also referred to as lecithinase B, lysolecithinase, and phospholipase B) catalyzes the hydrolysis of a 2-lysophosphatidylcholine to produce glycerophosphocholine and a fatty acid anion. 

LYSOPHOSPHOLIPASE 2-Lysophosphatidylcholine, LYSOPHOSPHOLIPASE LYSOPHOSPHOLIPASE LYSOPHOSPHOLIPASE D Lysopine,... 

Arnsdorff MF, Sawick GJ The effects of lysophosphatidylcholine A toxic metabolite of ischemia on the components of cardiac excitability in sheep Purkinje fibers. Circ Res 1981 49 16-30. 

Table 1.5 Equilibrium yield and equilibrium constants (K0) in the synthesis of phosphatidylcholine from lysophosphatidylcholine and oleic acid (800mM) at different water activities. Data from Ref. [29].

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