The pentacyclic triterpene Lupeol switches M1 macrophages to M2 and ameliorates experimental inflammatory bowel disease.

BACKGROUND: Inflammatory bowel disease (IBD), including ulcerative colitis and Crohn's disease, is a chronic inflammatory disease in the lower gastrointestinal tract. Mounting evidence suggests that the predominance of the classically activated (M1) macrophages versus the alternatively activated (M2) macrophages plays a role in the progression of IBD. Thus, agents able to shift pro-inflammatory M1 macrophages to anti-inflammatory M2 macrophages may be beneficial to IBD. The pentacyclic triterpene Lup-20(29)-en-3ß-ol (Lupeol), a potent anti-inflammatory natural product, has been shown to inhibit pro-inflammatory cytokine production, suggesting it is potentially able to modulate macrophage polarization, thereby beneficial to IBD. METHODS: CD4(+) monocytes were differentiated to M1 or M2 macrophages, which were cocultured with epithelial cell lines, T84 and Caco-2, in the absence or presence of Lupeol (10µM). Experimental colitis was induced with dextran sodium sulfate (DSS), with or without oral administration of Lupeol (50mg/kg, q.d.). Cytokines were measured with Luminex kits. M1/M2 genes were measured with real-time polymerase chain reaction. Macrophage phenotypes were defined by measuring M1 and M2 markers with confocal microscopy. Proteins were measured with Western blotting, while cell surface markers were measured with confocal microscopy or flow cytometry. Histology was evaluated with H&E staining. RESULTS: Treatment of M1 macrophages with Lupeol resulted in a marked decrease in the production of pro-inflammatory cytokines, including IL-12, IL6, IL-1ß and TNFα, and a marked increase in the production of IL-10, an anti-inflammatory cytokine. This was associated with a down-regulation of CD86, a typical marker of M1 macrophages, and an up-regulation of CD206, a typical M2 macrophage marker. IRF5, a transcription factor that is critically involved in M1 polarization, was down-regulated in M1 macrophages after being incubated with Lupeol, associated with a marked decrease in the phosphorylation of p38 mitogen activated protein kinase. Coculture of epithelial cells with M1 macrophages resulted in down-regulation of the tight junction protein ZO-1 and disruption of epithelial integrity, which were blocked by Lupeol treatment of the M1 macrophages. Moreover, oral administration of Lupeol to dextran sulfate sodium (DSS)-induced colitis mice resulted in mitigated intestinal inflammation and increased survival from lethal colitis, associated with decreased expression of M1-related genes and increased expression of M2-related genes. CONCLUSION: Lupeol ameliorates experimental inflammatory bowel disease through, at least in part, inhibiting M1 and promoting M2 macrophages.

[Comparative study on irritable bowel syndrome treated with acupuncture and western medicine].

OBJECTIVE: To compare the differences in the therapeutic effect on irritable bowel syndrome (IBS) between acupuncture at Tianshu (ST 25) and Dachangshu (BL 25) and western medication with Trimebutine Maleate. METHODS: Forty cases were divided randomly into an acupuncture group and a western medication group, 20 cases in each one. In acupuncture group, acupuncture was applied to Tianshu (ST 25) and Dachangshu (BL 25). Ziwu Daojiu needling technique was adopted, once daily. In western medication group, Trimebutine Maleate capsule was administered, 2 capsules in each time, 3 times per day. The assessment on the therapeutic effect was performed in 4 weeks of treatment in two groups. RESULTS: As compared with those before treatment, the time of abdominal pain, the frequency of abdominal pain, the morbidity of abnormal stool appearance, the morbidity of defecation abnormality, the morbidity of mucus stool and the score of bloating or abdominal pain on bowel movement were all reduced after treatment in two groups (all P < 0.01). The results in acupuncture group were much more significant than those in western medication group (the total score: 16.70 +/- 2.40 vs 15.70 +/- 3.01, P < 0.01). The total effective rate in acupuncture group was 95.0% (19/20), which was superior to that of 70.0% (14/20) in western medication group (P < 0.05). CONCLUSION: Acupuncture at Tianshu (ST 25) and Dachangshu (BL 25) may remarkably relieve the clinical symptoms of IBS and its efficacy is superior to that of oral medication with Trimebutine Maleate.