Betulinic acid attenuates T-2 toxin-induced lung injury by activating Nrf2 signaling pathway and inhibiting MAPK/NF-κB signaling pathway.

T-2 toxin, a type-A trichothecene mycotoxin, exists ubiquitously in mildewed foods and feeds. Betulinic acid (BA), a pentacyclic triterpenoid derived from plants, has the effect of relieving inflammation and oxidative stress. The purpose of this study was to investigate whether BA mitigates lung impairment caused by T-2 toxin and elucidate the underlying mechanism. The results indicated that T-2 toxin triggered the inflammatory cell infiltration, morphological alterations and cell apoptosis in the lungs. It is gratifying that BA ameliorated T-2 toxin-caused lung injury. The protein expression of nuclear factor erythrocyte 2-related factor 2 (Nrf2) pathway and the markers of antioxidative capability were improved in T-2 toxin induced lung injury by BA mediated protection. Simultaneously, BA supplementation could suppress T-2 toxin-induced mitogen-activated protein kinase (MAPK)/nuclear factor-kappa B (NF-κB)-dependent inflammatory response and mitochondrial apoptotic pathway. Therefore, T-2 toxin gave rise to pulmonary toxicity, but these changes were moderated by BA administration through regulation of the Nrf2/MAPK/NF-κB pathway, which maybe offer a viable alternative for mitigating the lung impairments caused by the mycotoxin.

Betulinic acid protects against renal damage by attenuation of oxidative stress and inflammation via Nrf2 signaling pathway in T-2 toxin-induced mice.

Betulinic acid (BA) is a pentacyclic triterpenoid compound with potential antioxidant and anti-inflammatory effects. In this study, T-2 toxin was injected intraperitoneally in mice to establish kidney damage model and to evaluate the protective effects of BA and further reveal the molecular mechanism. BA pretreatment inhibited the T-2 toxin-stimulated increase in serum Crea, but showed no significant effect on serum Urea. BA pretreatment alleviated excessive glomerular hemorrhage and inflammatory cell infiltration in kidneys caused by T-2 toxin. Moreover, pretreatment with BA mitigated T-2 toxin-induced renal oxidative damage by up-regulating the activities of SOD and CAT, and the content of GSH, while down-regulating the accumulation of ROS and MDA. Meanwhile, BA pretreatment markedly attenuated T-2 toxin-induced renal inflammatory response by decreasing the mRNA expression of IL-1ß, TNF-α and IL-10, and increasing IL-6 mRNA expression. Furthermore, mechanism research found that pretreatment with BA could activate Nrf2 signaling pathway. It was suggested that BA ameliorated the oxidative stress and inflammatory response of T-2 toxin-triggered renal damage by activating the Nrf2 signaling pathway.

Betulinic acid attenuates cyclophosphamide-induced intestinal mucosa injury by inhibiting the NF-κB/MAPK signalling pathways and activating the Nrf2 signalling pathway.

Betulinic acid (BA), a pentacyclic triterpenoid, has been associated with several biological effects, such as antioxidant, anti-inflammatory and antiviral activities. Previous studies have demonstrated that BA has the ability to alleviate intestinal mucosal damage, however, the potential mechanism associated with the effect has not been reported. This study aimed to investigate the possible protective mechanism of BA against cyclophosphamide (CYP)-induced intestinal mucosal damage. Here, we found that BA pretreatment prevented intestinal mucosal barrier dysfuction from CYP-challenged mice by repairing the intestinal physical, chemical, and immune barriers. Moreover, BA treatment suppressed the CYP-induced oxidative stress by activating the nuclear factor erythroid 2 [NF-E2]-related factor (Nrf2) pathway blocked reactive oxygen species (ROS) accumulation. In addition, BA inhibited CYP-triggered intestinal inflammation through down-regulating the nuclear transcription factor kappa B (NF-κB)/mitogen-activating protein kinase (MAPK) pathways. Furthermore, BA pretreatment reduced intestinal apoptosis by blocking ROS-activated mitochondrial apoptotic pathway. Overall, the current study demonstrated the protective effect of BA against CYP-caused intestinal mucosal damage by regulating the Nrf2 and NF-κB/MAPK signalling pathways, which may provide new therapeutic targets to attenuate intestinal impairment and maintain intestinal health.

γ-Oryzanol suppresses cell apoptosis by inhibiting reactive oxygen species-mediated mitochondrial signaling pathway in H2O2-stimulated L02 cells.

γ-Oryzanol, a mixture of ferulic acid esters of plant sterols and triterpene alcohols existed in rice bran oil, can ameliorate lipid metabolism and enhance antioxidant activity. In this study, we used hydrogen peroxide (H2O2)-induced injury in human hepatic L02 cells to investigate the mechanisms involved in the hepatoprotective activity of γ-oryzanol. The injuries produced by H2O2 in L02 cells include increased levels of malondialdehyde (MDA) and intracellular reactive oxygen species (ROS), decreased activities of superoxide dismutase (SOD) and catalase (CAT), loss of mitochondrial membrane potential (MMP), increased protein expressions of caspase-9 and caspase-3, and induced apoptosis. Pretreatment with γ-oryzanol enhanced the ROS scavenging activity of endogenous antioxidant enzymes and decreased lipid peroxidation in H2O2 treated cells. Moreover, pretreatment with γ-oryzanol inhibited H2O2-induced apoptosis by restoring MMP, upregulating the expression ratio of Bcl-2/Bax, and inhibiting the activation of caspase-9 and caspase-3. These findings show that γ-oryzanol can prevent H2O2-induced apoptosis by suppressing intracellular accumulation of ROS and impeding ROS-activated mitochondrial apoptotic pathway.

Anti-inflammatory effect and potential mechanism of betulinic acid on λ-carrageenan-induced paw edema in mice.

λ-Carrageenan (Carr), a seaweed polysaccharide, is used as a proinflammatory agent in research. Betulinic acid (BA), a naturally occurring pentacyclic triterpenoid, exerts immunomodulatory, antioxidant, anti-inflammatory, antitumor, anti-malarial and anti-HIV effects. The aim of this study was to investigate whether BA exerts anti-inflammatory effect against Carr-induced paw edema in mice, and how BA could mediate the expression of inflammation-associated MAPK-COX-2-PGE2 signal pathway. BA pretreatment significantly reduced the inflammatory response to Carr-induced paw edema, especially at 4 h after injection. BA reduced the serum levels of pro-inflammatory cytokines, such as IL-1α, IL-1ß, IL-5, IL-6, GM-CSF, KC, MCP-1 and PGE2 in Carr-treated mice, and increased those of anti-inflammatory cytokines, such as IL-12. It also increased SOD, CAT and GSH-Px activities, and GSH content, and reduced MDA content in the liver of Carr-treated mice. Besides, BA reduced neutrophil infiltration in the basal and subcutaneous layers of the paw of Carr-treated mice, decreased the expression of COX-2 protein, and reduced the phosphorylation of JNK, p38 and ERK1/2. These results indicated that the protective effect of BA on Carr-induced paw edema might be due to its alleviation of inflammatory response and inhibition of oxidative stress, possibly by inhibiting MAPK-COX-2-PGE2 signaling pathway activation.

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

BACKGROUND: 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. METHODS: 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. RESULTS: 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-1ß (MIP-1ß) 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-1ß 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. CONCLUSIONS: BA might be considered as an effective agent in the amelioration of the intestinal mucosal resulting from CYP treatment.