Protective effects of betulinic acid on intestinal mucosal injury induced by cyclophosphamide in mice.

Betulinic acid (BA) is a plant-derived pentacyclic triterpenoid with a variety of biological activities. The purpose of this study was to assess the potential protective role of BA against intestinal mucosal injury induced by cyclophosphamide (CYP) treatment.Mice were pretreated with BA daily (0.05, 0.5, and 5.0 mg/kg) for 14 days, then injected intraperitoneally with CYP (50 mg/kg) for 2 days.BA pretreatment reduced the contents of malondialdehyde (MDA) and glutathione (GSH), decreased the activity of superoxide dismutase (SOD) in small intestine, increased villus hight/crypt depth ratio and restored the morphology of intestinal villi in CYP-induced mice. Moreover, BA pretreatment could significantly down-regulate the levels of pro-inflammatory cytokines interleukin-5 (IL-5), IL-17, IL-12(P70) and tumor necrosis factor α (TNF-α), reduced production of chemokines macrophage inflammatory protein-1α (MIP-1α), macrophage inflammatory protein-1β (MIP-1β) and regulated upon activation, normal T-cell expressed and secreted (RANTES), and enhanced the levels of anti-inflammatory such as IL-2 and IL-10 in serum, and decreased the mRNA expressions of IL-1β and TNF-α in intestine of CYP-induced mice. Furthermore, RT-PCR demonstrated that BA improved intestinal physical and immunological barrier in CYP-stimulated mice by enhancing the mRNA expressions of zonula occluden 1 (ZO-1) and Claudin-1.BA might be considered as an effective agent in the amelioration of the intestinal mucosal resulting from CYP treatment.