An isomeric mixture of novel cerebrosides isolated from Impatiens pritzellii reduces lipopolysaccharide-induced release of IL-18 from human peripheral blood mononuclear cells.

An isomeric mixture of two cerebrosides, soya-cerebrosides I and II, was isolated from an ethno drug, the rhizomes of Impatiens pritzellii Hook. f. var. hupehensis Hook. f., and their structures were identified by spectroscopic (NMR, MS) analysis. In order to determine the immunomodulatory activities of soya-cerebrosides I and II, the effects of the mixture of cerebrosides (MC) on cytotoxicity of human peripheral blood mononuclear cells (PBMC) and the inhibitory activities to lipopolysaccharide (LPS)-induced interleukin (IL)-18 in PBMC were studied. The MC at concentrations of 10 and 1 microM, without toxicity to PBMC in 24 h, showed obvious inhibitory activity on IL-18 secretion. Because of this effect of modulating the cellular immune response, soya-cerebrosides I and II were considered to be the active substances of this ethno drug.