[Membranotropic effect of some triterpene glycosides possessing immunostimulating properties].
The peculiarities of the interaction between cell membrane lipids and triterpene glycosides from holothurians Apostichopus japonicus S. and Cucumaria japonica (holotoxin A1 and cucumarioside A2-2, respectively) were studied in comparison with plant saponins from Quillaja saponaria, known as hemolytic, adjuvant, and structure-forming components of immunostimulating complexes. Similar to Quillaja saponins, the sea glycosides, holotoxin A1 and cucumarioside A2-2 were shown to possess a high hemolytic activity (2.6 and 3 microg/ml, respectively) and sterol-depending membranotropic effect mediated by the formation of nonbilayer sterol-lipid-glycoside complexes. At the same time, cucumarioside A2-2 bound exogenic cholesterol only in the presence of membrane lipids, such as phosphatidylcholine or monogalactosyldiacylglycerol, in contrast to Quillaja saponins and holotoxin A1, which bound cholesterol in the molar ratios 1:2 and 1:8, respectively. Moreover, in all cases, tree-component complexes containing cholesterol, lipid, and glycoside exhibited a lower hemolytic activity compared with two-component sterol-glycoside complexes. It was concluded that the hydrophobic medium of cell membranes performs a potentiative role in the effective interaction between triterpene glycosides and "sterol receptors". A method for decreasing the toxicity of membranotropic holothurian glycosides possessing the immunomodulating properties was suggested.
Lee
I A
IA
Popov
A M
AM
Kostetskiĭ
E Ia
EIa
Sanina
N M
NM
Mazeĭka
A N
AN
Boguslavskiĭ
V M
VM
D000818:Animals; D002462:Cell Membrane / Q000378:metabolism*; D002784:Cholesterol / Q000378:metabolism; D006027:Glycosides / Q000494:pharmacology*; D006461:Hemolysis / Q000187:drug effects; D007155:Immunologic Factors / Q000494:pharmacology*; D008563:Membrane Lipids / Q000378:metabolism; D051379:Mice; D031990:Quillaja / Q000737:chemistry; D047528:Stichopus; D014315:Triterpenes / Q000494:pharmacology*
D006027:Glycosides; D007155:Immunologic Factors; D008563:Membrane Lipids; D014315:Triterpenes; C001883:stichoposide; C033504:cucumarioside; D002784:Cholesterol