Abstract
For decades, the pharmacological identity of Panax ginseng has been primarily attributed to triterpenoid saponins known as ginsenosides. However, accumulating evidence indicates that ginseng also contains a structurally distinct lipid-protein complex, termed gintonin, enriched in lysophosphatidic acid (LPA) species. Unlike ginsenosides, which predominantly exert modulatory effects on membrane dynamics and intracellular kinase pathways, gintonin directly activates LPA G protein-coupled receptors (GPCRs), thereby inducing rapid phospholipase C (PLC) activation and intracellular Ca(2+) mobilization. Biochemical analyses have identified major LPA species within the gintonin fraction, including C16:0, C18:0, and C18:1, stabilized within a proteinaceous matrix that may influence receptor engagement kinetics. Pharmacological studies demonstrate that gintonin preferentially activates LPA(1) and LPA(3) receptor subtypes, triggering downstream signaling cascades involving MAPK, PI3K/Akt, and Rho pathways. These receptor-mediated effects occur on a rapid temporal scale, distinguishing gintonin from the slower transcriptional and kinase-modulating actions of ginsenosides. In this review, we synthesize current evidence regarding the chemical architecture, receptor pharmacology, and signaling dynamics of gintonin and propose a dual signaling framework in which steroid-like saponins and lipid GPCR ligands represent complementary molecular axes within P. ginseng. Recognition of this layered signaling organization refines the molecular understanding of ginseng biology and highlights gintonin as a unique plant-derived GPCR ligand system.