Ethanol extract of Centella asiatica alleviated dextran sulfate sodium-induced colitis: Restoration on mucosa barrier and gut microbiota homeostasis.

Ulcerative colitis (UC) is a relapsing inflammatory disease that still demands for effective remedies due to various adverse effects of the current principal treatments. Centella asiatica is a traditional medical herb with long application history in anti-inflammation. To explore the anti-inflammatory effect and possible mechanism of C. asiatica ethanol extract (CA) in a murine colitis model induced by dextran sulfate sodium (DSS). CA was analyzed by high performance liquid chromatograph (HPLC). The colitis model was induced by free access to 3% DSS in distilled water for 7 days. CA (100, 200, and 400 mg/kg) and 5-aminosalicylic acid (5-ASA, 400 mg/kg) were administrated by gavage during the 7-day DSS challenge. At the end of experiment, mice were sacrificed and the brain, colon and cecum contents were harvested for analysis. Colitis was evaluated by disease activity index (DAI), colon length and colon lesion macroscopic score with hematoxylin-eosin staining. Myeloperoxidase (MPO) activity in colon and 5-hydroxytryptamine (5-HT) in brain were determined by ELISA. Tight junction protein expressions (ZO-1, E-Cadherin, Claudin-1) and c-Kit in colon were assessed by western blot and immunohistochemistry, respectively. Microbiota of cecum content was analyzed by 16S rRNA sequencing. Data showed that with recovery on the colon length and histological structure, CA prominently decreased DAI and macroscopic score for lesion in the suffering mice. CA relieved the colitis by suppressing inflammatory cell infiltration with decreased MPO activity in the colon, and up-regulated the expression of tight junction protein (ZO-1, E-cadherin) to enhance the permeability of intestinal mucosa. Moreover, CA restored intestinal motility by promoting c-Kit expression in the colon and 5-HT in the brain. Moreover, CA was able to reshape the gut microbiota in the suffering mice. It increased the α-diversity and shifted the community by depleting the colitis-associated genera, Helicobacter, Jeotgalicoccus and Staphylococcus, with impact on several metabolism signaling pathways, which possibly contributes to the renovation on the impaired intestinal mucosal barrier. CA displayed the anti-inflammatory activity against the DSS-induced colitis, which would possibly rely on the restoration on mucosa barrier and gut microbiota homeostasis, highlights a promising application of C. asiatica in the clinical treatment of UC.

Li H ，Chen X ，Liu J ，Chen M ，Huang M ，Huang G ，Chen X ，Du Q ，Su J ，Lin R ... -  《-》

2,3,5,4'-Tetrahydroxystilbene-2-O-β-D-glucoside, a major bioactive component from Polygoni multiflori Radix (Heshouwu) suppresses DSS induced acute colitis in BALb/c mice by modulating gut microbiota.

Inflammatory bowel disease (IBD) includes ulcerative colitis (UC) and Crohn's disease (CD), which is a common idiopathic digestive disease without a specific cure or treatment for improvement. Because Polygoni multiflori Radix has a traditional medicinal use to treat intestinal diseases, and the water extract of this herbal medicine had a positive influence on dextran sulfate sodium (DSS) induced UC model in our study. Meanwhile 2,3,5,4'-tetrahydroxystilbene-2-O-β-D-glucoside (TSG) as the major component of the water extract of Polygoni multiflori Radix with yield of more than 10% exhibited the remarkable anti-inflammatory activity in vivo and in vitro, we predicted that TSG may contribute to benefit intestinal tract presented by the water extract of Polygoni multiflori Radix. Therefore, the present study aims to explore the pharmacological effect of this compound on UC model and its possible mechanism to regulate intestinal function through gut microbiota. Ulcerative colitis model was established in BALb/c mice by continuously administrating 3% (w/v) DSS aqueous solution for one week. The disease activity index (DAI), colon length, histopathological examination by H&E and the levels of tight junction proteins (TJP) by immunofluorescence staining were performed in ulcerative colitis model following the protocol. Furthermore, the levels of main inflammatory factors like TNF-α, IL-β, IL-6, and IL-10 were analyzed by the ELIZA kits for the further confirmation of anti-inflammatory activity of TSG on ulcerative colitis model. Finally, 16S rDNA sequencing technology was conducted to explore the composition and relative abundance of gut microbiota of different treatment groups. TSG treatments effectively increased body weight about 5% of those in DSS group (p < 0.001) as well remarkably reduced the DAI scores to the 50% of those in DSS group (p < 0.001) in the UC model. TSG treatments of either 25 mg/kg (TSG-25) or 100 mg/kg (TSG-100) dosage restored epithelial barrier structure and exhibited obviously intact colon histology with reduced signs of inflammatory cells infiltration, preserved epithelia barrier, restored crypt structure, and increased numbers of goblet cells. TSG treatments could markedly lessen the histopathologic score two or three times than those in DSS group (p < 0.001). Especially for TSG-100 treatment, the fluorescence intensity of ZO-1 and Occludin were nearly back to 80% of those in normal group, and were 1.5 times more than those in the DSS group (p < 0.001). Additionally, direct evidence pointed to TSG as a therapeutically active molecule in the prevention and treatment of UC by significantly reducing the production of these pro-inflammatory cytokines like TNF-α, IL-1β, and IL-6 (p < 0.05-0.001) and increasing the levels of anti-inflammatory cytokine IL-10 (p < 0.05-0.001). Finally, it was found TSG treatments significantly raised the relative abundances of Firmicutes and Bacteroidetes with a dose-dependently and improved the homeostasis of the gut microbiota composition which disrupted by DSS through increasing genus level Lachnospiraceae_NK4A136 and decreasing genus level of Helicobacter, Bacteroides, Parabacteroides. The present results suggested that TSG treatments had a desirable pharmacological effect on acute colitis induced by DSS in the mice as well showed the possible mechanism relate to improve the intestinal function through balancing the gut microbiota of intestinal flora.

He X ，Liu J ，Long G ，Xia XH ，Liu M ... -  《-》

Intestinal anti-inflammatory effects of fuzi-ganjiang herb pair against DSS-induced ulcerative colitis in mice.

Fuzi and ganjiang are widely used as traditional Chinese medicines (TCM) in China, Korea, Japan, and many other southeast Asian countries for treating ulcerative colitis (UC), emesis and heart failure for more than 1800 years. However, the underlying mechanism of fuzi, ganjiang and fuzi-ganjiang herb pair is still unclear. In our study, we explored the therapeutic effects of fuzi, ganjiang and fuzi-ganjiang herb pair against dextran sulfate sodium (DSS)-induced UC in mice model, along with the relevant mechanism. The contents of each marker compound in fuzi decoction (FD), ganjiang decoction (GD) and fuzi-ganjiang decoction (FGD) were determined using LC-MS/MS. During the experiment, bodyweight changes in each group were monitored every 5 days. On the day of sacrifice, colonic length, disease activity index (DAI) and spleen weight were also evaluated and histopathological examination was performed through hematoxylin & eosin (H&E) staining. The levels of myeloperoxidase (MPO) and inflammatory cytokines in colon tissues were determined by enzyme-linked immunosorbent assay (ELISA), and then the relative mRNA productions of inflammatory mediators, such as MPO, inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 were measured by real-time polymerase chain reaction (PCR). Involvement of MAPK, STAT3 and NF-κB signaling pathways in the pathogenesis of UC was determined in each group using Western Blot (WB) analysis. Compared with fuzi and ganjiang single decoction, the content of the alkaloids derived from fuzi (especially the diester alkaloid with strong toxicity, hypaconitine) in fuzi-ganjiang herb pair decoction was reduced. Additionally, the 6-gingerol, which was not found in ganjiang single decoction, was retained in fuzi-ganjiang herb pair decoction. FD, GD, and FGD significantly restored the bodyweight reduction, colon shortening, DAI elevation, splenomegaly and histological score in DSS-induced UC mice. Furthermore, except for the failure of low dosage of ganjiang decoction (GD-L) on IL-17A, all FD, GD and FGD significantly inhibited the production of MPO and inflammatory cytokines, such as IFN-γ, TNF-α, IL-1β, IL-6, IL-10 and IL-17A, and suppressed the relative expression of inflammatory mediators, such as MPO, iNOS and COX-2 mRNA in colon tissues of DSS-induced mice. According to WB analysis, fuzi, ganjiang and fuzi-ganjiang combination inhibited the activation of MAPK, NF-κB and STAT3 signaling pathways. Our study demonstrated that fuzi, ganjiang and fuzi-ganjiang combination possess prominent anti-inflammatory activities against DSS-induced UC mice; the involved mechanism may be related to inhibition the activation of MAPK, NF-κB, and STAT3 signaling pathways.

Huang C ，Dong J ，Jin X ，Ma H ，Zhang D ，Wang F ，Cheng L ，Feng Y ，Xiong X ，Jiang J ，Hu L ，Lei M ，Wu B ，Zhang G ... -  《-》

Main active components of Jiawei Gegen Qinlian decoction protects against ulcerative colitis under different dietary environments in a gut microbiota-dependent manner.

As an effective drug against acute enteritis diarrhea, Gegen Qinlian decoction (GQD) has a history of 2000 years. However, the potential molecular mechanism through which GQD could protect intestinal barrier from ulcerative colitis (UC) still remains undefined. As an important part of the homeostasis of the colon, gut microbiota is closely related to the dynamic evolution of the surrounding environment and the adjustment of dietary structure. At present, the effectiveness and mechanism of Jiawei Gegen Qinlian decoction against UC in different dietary environments are not clear. Here, the main active components of Jiawei Gegen Qinlian Decoction (PBM), were selected to construct a reasonable and effective compound scheme. We adopted "5% dextran sulfate sodium (DSS)" and "high temperature and humidity + high sugar and high fat + alcohol + 5%DSS" to induce UC rat models in general environment and UC rat models in Lingnan area, respectively. Then, we examined the therapeutic effects of PBM (89.96 mg/kg and 179.92 mg/kg) on two kinds of UC rats. The role of gut microbiota in the anti-UC effect of PBM was identified by intestinal flora consumption and fecal microbiota transplantation (FMT) experiments. Subsequently, we monitored the alterations of gut microbiota and fecal metabolism in the rat colon by 16Sr DNA technique and targeted metabonomics, respectively. The colon inflammation of the PBM-treated and the FMT-treated rats both showed significant relief, as evidenced by a reduction in body weight loss, bloody stool, diarrhea, disease activity index (DAI) score, shortening of colon length as well as decreased colon histology damage. Interestingly enough, the depletion of intestinal flora took away the protective effect of PBM, confirming the importance of intestinal flora in the anti-UC effect of PBM. Then our findings suggested that PBM could not only regulate the gut microbiota by increasing Akkermansia and Romboutsia but also decrease Escherichia-Shigella. More importantly, PBM could increase the production of propionate and total short-chain fatty acids (SCFAs) in colitis rats, regulate medium and long chain fatty acids (M-LCFAs), maintain bile acids (BAs) homeostasis, and regulate amino acids (AAs) metabolism. The transformation of intestinal environment might be related to the upregulation of anti-inflammation, anti-oxidation and tight junction protein expression in colonic mucosa. In summary, PBM showed potential for anti-UC activity through gut microbiota dependence and was expected to be a complementary and alternative medicine herb therapy.

Li Q ，Cui Y ，Xu B ，Wang Y ，Lv F ，Li Z ，Li H ，Chen X ，Peng X ，Chen Y ，Wu E ，Qu D ，Jian Y ，Si H ... -  《-》

Tauroursodeoxycholic Acid Reverses Dextran Sulfate Sodium-Induced Colitis in Mice via Modulation of Intestinal Barrier Dysfunction and Microbiome Dysregulation.

Ulcerative colitis (UC) is an immune-mediated inflammatory disease that can lead to persistent damage and even cancer without any intervention. Conventional treatments can alleviate UC symptoms but are costly and cause various side effects. Tauroursodeoxycholic acid (TUDCA), a secondary bile acid derivative, possesses anti-inflammatory and cytoprotective properties for various diseases, but its potential therapeutic benefits in UC have not been fully explored. Mice were subjected to colitis induction using 3% dextran sulfate sodium (DSS). The therapeutic effect of TUDCA was evaluated by body weight loss, disease activity index (DAI), colon length, and spleen weight ratio. Tissue pathology was assessed using H&E staining, while the levels of pro-inflammatory and anti-inflammatory cytokines in colonic tissue were quantified via ELISA. Tight junction proteins were detected by immunoblotting and intestinal permeability was assessed using fluorescein isothiocyanate (FITC)-dextran. Moreover, the gut microbiota was profiled using high-throughput sequencing of the 16S rDNA gene. TUDCA alleviated the colitis in mice, involving reduced DAI, attenuated colon and spleen enlargement, ameliorated histopathological lesions, and normalized levels of pro-inflammatory and anti-inflammatory cytokines. Furthermore, TUDCA treatment inhibited the downregulation of intestinal barrier proteins, including zonula occludens-1 and occludin, thus reducing intestinal permeability. The analysis of gut microbiota suggested that TUDCA modulated the dysbiosis in mice with colitis, especially for the remarkable rise in Akkermansia TUDCA exerted a therapeutic efficacy in DSS-induced colitis by reducing intestinal inflammation, protecting intestinal barrier integrity, and restoring gut microbiota balance. SIGNIFICANCE STATEMENT: This study demonstrates the potential therapeutic benefits of Tauroursodeoxycholic acid (TUDCA) in ulcerative colitis. TUDCA effectively alleviated colitis symptoms in mice, including reducing inflammation, restoring intestinal barrier integrity and the dysbiosis of gut microbiota. This work highlights the promising role of TUDCA as a potentially alternative treatment, offering new insights into managing this debilitating condition.

Luo L ，Zhao Y ，Zhang G ，Dong S ，Xu Y ，Shi H ，Zhang M ，Liu X ，Wang S ，Luo H ，Jing W ... -  《-》