RESUMEN
Four new resin glycosides having macrolactone structures (jalapins), murasakimasarins I-IV, were isolated from the tubers of Ipomoea batatas (L.) Lam. ('Murasakimasari', Convolvulaceae), along with three known glycosides. Their structures were determined on the basis of spectroscopic data as well as chemical evidence. Murasakimasarin III is the first representative of a resin glycoside with 10-methylundecanoic acid as the component organic acid.
Asunto(s)
Glicósidos/química , Ipomoea batatas/química , Resinas de Plantas/química , Estructura MolecularRESUMEN
Oxidatively modified low-density lipoprotein (OxLDL) is present in atherosclerotic lesions and has been proposed to play an important role in atherogenesis. In the present study, in order to clarify the structure-binding activity relationship of Asp-hemolysin-related peptides to OxLDL, we investigated the interaction between Asp-hemolysin-related peptides consisting of 4 to 29 amino acid residues and OxLDL. The incubation of OxLDL with each Asp-hemolysin-related peptide resulted in the formation of an Asp-hemolysin/OxLDL complex. In particular, the tetrapeptide, YKDG (P-4), bound to OxLDL and inhibited the OxLDL-induced macrophage proliferation in a dose-dependent manner. Furthermore, we demonstrated that lysophosphatidylcholine (LysoPC) extracted from OxLDL inhibited the binding of P-21 to OxLDL in a dose-dependent manner and synthetic [14C]LysoPC bound to P-21. We propose here that the YKDG region is one of the important sites for the binding of these peptides to OxLDL, and LysoPC as a typical lipid moiety of OxLDL is attributed to the binding of OxLDL to these peptides.