Lecithin liposomes

Satue-Gracia MT, Heinonen M and Frankel EN. 1997. Anthocyanins as antioxidants on human low-density lipoprotein and lecithin-liposome systems. J Agric Food Chem 45 3362—3367. 

Miyoshi, H., Nishioka, T. and Fujita, T. (1986). Quantitative analysis of effects of substituted phenols on membrane characteristics of lecithin liposomes, Bull. Chem. Soc. Jpn., 59, 1099-1107. 

Heinonen, M. et al., Effect of protein on the antioxidant activity of phenolic compounds in a lecithin-liposome oxidation system, J. Agric. Food Chem., 46, 917, 1998. 

Figure 9.25 Permeability of some common substances into lecithine liposomes (T > Tm, pH = 7). Generally, the permeability for polar, charged molecules and for molecules with a high molecular weight is small. Maximum permeability is when r= 77,.

Yomo, Urabe and coworkers (Yu et al, 2001), for example, reported the expression of a mutant GFP (actually the pET-21-GFPmutl-His6 mutant) in lecithin liposomes. Large GFP-expressing vesicles, prepared by the film hydration method, were analyzed using flow cytometry as well as confocal laser microscopy. 

As already mentioned, early attempts have been focused on the enzymatic production of lecithin in lecithin liposomes (Schmidli et al, 1991). The metabolic pathway was the so-called Salvage pathway, which converts glycerol-3-phosphate to phosphatidic acid, then diacylglycerol and hnally phosphatidylcholine. Production of the cell boundary from within corresponds to autopoiesis and would close the circle between minimal cell and the autopoietic view of cellular life. 

The internal synthesis of lecithin in lecithin liposomes would be a signihcant step forwards. In parhcular, it would be very intereshng to see, given a certain excess of the enzymes, for how many generahons the cell self-reproduction could go on. It is clear, however, that after a certain number of generations, the system would undergo death by dilution. ... 

Experimental design Groups of 8-11 male rats were treated with 0, 1, 3, or 6 mg/kg/day doses of an unspecified mixture of PBBs in lecithin liposomes by gavage for 10 days. Plasma was assayed on treatment days 10 and 20. Other end points were evaluated on treatment day 20 these included plasma TSH levels, 5-hour thyroid uptake of I, incorporation of into monoiodotyrosine, diiodotyrosine, I, or T4, amount of intrathyroidal iodide, thyroid and liver weights, and body weights. Differences between mean values for the measured parameters in the control and PBB-treated groups were analyzed with the Student s Mest, with aP value of 0.05 considered as statistically significant. 

Imura, T., Otake, K., Hashimoto, S., Gotoh, T., Yuasa, M., Yokoyama, S., Sakai, H., Rathman, J. F., and Abe, M. (2003). Preparation and physicochemical properties of various soybean lecithin liposomes using supercritical reverse phase evaporation meOnWsfcids. Surf. B-Biointerfaces, 27, 133-140. 

Figure 7. Oxidative polyamide fluorescence emission spectrum from oxidized soy lecithin liposomes (excitation wavelength, 360 nm).

Figure 10. Antioxidant evaluation by oxidative polyamide fluorescence from soy lecithin liposomes. Key O, blank , lecithin plus hematin A, lecithin-hematin...

We reported (35) on a fluorescence test of the relative effectiveness of antioxidants in oxidizing soy lecithin liposomes (sonicated microdispersions). 

Inhibited lipid peroxidation induced by radiation in egg lecithin liposomes and by Fe2+ in mitochondria 616... 

Fig. 4.17 Signal broadening (Avlj/2, mm) of various spin systems of chlorphentermine (a-c) at constant liposome concentration (1.2mg/mL) as a function of increasing NaCI concentration (0-6 mg/mL). The lowest symbols at zero NaCI concentration represent the control line width of the different proton resonance signals in the absence of both lecithin liposomes and NaCI. (Reprinted from Fig. 4 of ref. 135 with permission from Elsevier Science.)...

Fig. 10A-D. Freeze-fracture electron micrographs of mixed liposomes composed of lecithin and lipids 5 or 6 before and after mixing A image of lecithin liposomes containing lipid 5 or 6 before mixing B aggregation immediately following mixing of the complementary liposomes C,D images obtained after incubation for at least 15 minutes (taken from...

Studies on the antioxidant properties of anthocyanins on human low-density lipoprotein (LDL) and lecithin liposome systems in vitro showed that the inhibition of oxidation increased dose-dependently with antioxidant concentration. The oxidation was catalyzed by copper in the LDL system and the effects of the anthocyanins were explained by several antioxidant mechanisms including hydrogen donation, metal chelation and protein binding [33]. Anthocyanins also prevented the oxidation of ascorbic acid (vitamin C), through chelate formation with the metal ions, and finally by the formation of an ascorbic (copigment)-metal-anthocyanin complex [49]. 

Ferrous sulphate eneapsulated in soy lecithin liposomes has been used to deliver iron. These preparations have improved bioavailability compared to ferrous sulphate directly added in milk and dairy products (Boccio et al. 1997 Uicich et al. 1999). Albaldawi et al. (2005) reported that the addition of encapsulated haem iron in lecithin/cholesterol liposomes resulted in improved rheological properties of bread dough and the sensory properties of baked bread. 

Jain, M. K. and Wu, N. M. Effect of small molecules on the dipalmitoyl lecithin liposomal bilayer. Journal of Membrane Biology 54 157-201, 1977. 

AndreollTE. On the anatomy of amphotericin B-cholesterol pores in lipid bilayer membranes. Kidney Int 1973 4 337-45. DeKruijiff B, Demel RA. Polyene antibiotic-sterol interactions in membranes of Acholeplesma laidlawii cellsand lecithin liposomes. III. Molecular structure of the polyene antibiotic-cholesterol complexes. Biochem Biophys Acta 1974 339 57-70. HoIzRW.Theeffectsofthe polyene antibiotics nystatin and amphotericin Bon thin lipid membranes. Ann N Y Acad Sell 974 235 469-79. 

Strieker H, Muller H. The storage stability of dispersions of soybean-lecithin liposomes [in German]. Pharm Ind 1984 46 1175-1183. 

This research has been carried out in our laboratory and is still actively pursued— this is part of our enterprise in the direction of the minimal living cell. It is not the aim of this review to dwell upon this part. The interested reader is referred to our work concerned with enzymes in liposomes, in particular to the work dealing with lecithin-producing enzymes in lecithin liposomes, or the following work on enzymatic and molecular biological reaction taking place in vesicles and liposomes. " ... 

CETP activity can be measured in vitro by a variety of methods, conditions, and substrates, but a common method is to monitor the transfer of [ C]CE between HDL and LDL. The donor and receptor lipoproteins are separated by heparin-MnCl2 precipitation and aliquots are counted [66,72]. CETP activity is determined by the difference between CE transfer with and without CETP. Fielding and coworkers [74] have devised an equally useful method, measuring CE transfer from cholesterol-lecithin liposomes to sphingomyelin-cholesterol liposomes. 

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