Guchang Zhixie Wan protects mice against dextran sulfate sodium-induced colitis through modulating the gut microbiota in colon.

ETHNOPHARMACOLOGICAL RELEVANCE: Guchang Zhixie Wan (GC) is a traditional Chinese patent medicine used in the treatment of colitis in clinical trials. Though the notable effect of GC on colitis, the concrete mechanism of GC remain elusive. Emerging evidence showed that the imbalances of inflammatory cytokines and gut microbiota were both closely related to the initiation and progression of colitis. AIM OF THE STUDY: To elucidate the relationship between the protective effects of GC on colitis and gut microbiota. MATERIALS AND METHODS: Male Kunming (KM) mice were enrolled in our work to establish colitis model induced by dextran sulfate sodium (DSS). The colitis mice were randomly divided into different groups and treated orally with 125 mg/kg of sulfasalazine (positive control) and 25, 50, 100 mg/kg of GC for 7 days, respectively. Inflammation cytokines of IL-1ß, IL-4, IL-6, IL-8, IL-11, IL-12 and TNF-α were detected by ELISA analysis and the histological changes were detected by H&E staining. Gut microbiota diversity was analyzed by 16S rDNA sequencing. Metagenomes analysis were also conducted to reflect the protective effects of GC on colitis. RESULTS: The results of CAS (Clinical Activity Score) confirmed the protective effects of GC on colitis. After administration of GC, the levels of pro-inflammatory cytokines IL-1ß, IL-6, IL-8, IL-11, IL-12 and TNF-α were all decreased while the anti-inflammatory cytokines IL-4 was slightly increased, indicating that GC could down regulate pro-inflammatory cytokines. H&E staining revealed that GC could improve the histopathological structure of the colon tissue. The results of 16S rDNA sequences analysis showed that GC could decrease the relative abundance of Turicibacter and increase the relative abundance of Ruminococcaceae_UCG-005. CONCLUSION: GC greatly improve the health condition of colitis mice induced by DSS through improving the imbalances of inflammatory cytokines and gut microbiota.

Indigo Naturalis Ameliorates Dextran Sulfate Sodium-Induced Colitis in Mice by Modulating the Intestinal Microbiota Community.

Indigo naturalis (IN) is a traditional Chinese medicine, named Qing-Dai, which is extracted from indigo plants and has been used to treat patients with inflammatory bowel disease (IBD) in China and Japan. Though there are notable effects of IN on colitis, the mechanisms remain elusive. Regarding the significance of alterations of intestinal flora related to IBD and the poor water solubility of the blue IN powder, we predicted that the protective action of IN on colitis may occur through modifying gut microbiota. To investigate the relationships of IN, colitis, and gut microbiomes, a dextran sulfate sodium (DSS)-induced mice colitis model was tested to explore the protective effects of IN on macroscopic colitis symptoms, the histopathological structure, inflammation cytokines, and gut microbiota, and their potential functions. Sulfasalazine (SASP) was used as the positive control. Firstly, because it was a mixture, the main chemical compositions of indigo and indirubin in IN were detected by ultra-performance liquid chromatography (UPLC). The clinical activity score (CAS), hematoxylin and eosin (H&E) staining results, and enzyme-linked immunosorbent assay (ELISA) results in this study showed that IN greatly improved the health conditions of the tested colitis mice, ameliorated the histopathological structure of the colon tissue, down-regulated pro-inflammatory cytokines, and up-regulated anti-inflammatory cytokines. The results of 16S rDNA sequences analysis with the Illumina MiSeq platform showed that IN could modulate the balance of gut microbiota, especially by down-regulating the relative quantity of Turicibacter and up-regulating the relative quantity of Peptococcus. The therapeutic effect of IN may be closely related to the anaerobic gram-positive bacteria of Turicibacter and Peptococcus. The inferred metagenomes from 16S data using PICRUSt demonstrated that decreased metabolic genes, such as through biosynthesis of siderophore group nonribosomal peptides, non-homologous end-joining, and glycosphingolipid biosynthesis of lacto and neolacto series, may maintain microbiota homeostasis during inflammation from IN treatment in DSS-induced colitis.

Structural Features of Sulfated Glucuronomannan Oligosaccharides and Their Antioxidant Activity.

Glucuronomannan oligosaccharides (Gs) were derived from fucoidan, which was extracted from the brown alga Sargassum thunbergii. Sulfated glucuronomannan oligosaccharides (SGs) were obtained by the sulfation of Gs. NMR techniques were used to reveal that the order of sulfation was Man-C6 > Man-C4 > Man-C1R > GlcA-C3 > Man-C3 > GlcA-C2. Finally, the antioxidant activities (hydroxyl radical scavenging activity, superoxide radical scavenging activity, reducing power and DPPH radical scavenging activity) of Gs and SGs were determined. The findings showed that the higher the degree of polymerization, the better the activity, except for the hydroxyl radical scavenging activity. In addition, the higher the sulfate content, the lower the activities for the reducing power and DPPH radical scavenging activity. Opposite results were found for the superoxide radical scavenging activity. Finally, compared with fucoidan, most Gs and SGs had higher antioxidant activity, suggesting that they might be good candidates for antioxidants.