Oleanolic acid is a triterpenoid originally found in Vigna angularis and Trigonella foenum-graecum. Oleanolic acid exhibits anticancer, anti-inflammatory, anti-allergic, anti-resorptive, and anti-osteoporotic activities. In hypertrophic scar fibroblasts, oleanolic acid induces mitochondria-dependent apoptosis through the activation of p38 MAPK and JNK and increases in caspase expression. In melanoma cells, oleanolic acid decreases cell viability by inducing caspase 3-mediated apoptosis and inhibiting activity of EGFR. Additionally, in animal models, this compound inhibits eosinophil infiltration, airway inflammation, and production of IL-5, IL-13, IL-17, and IgE; this is through to be mediated by upregulation of Foxp3 and downregulation of GATA-3 and RORγt. In bone marrow macrophages, oleanolic acid inhibits RANKL-induced osteoclast differentiation and mature osteoclast differentiation; it also inhibits LPS-induced bone erosion in animal models.