Transcriptome profiling Revealed the potential mechanisms of Shen Lin Bai Zhu San n-butanol extract on DSS induced Colitis in Mice and LC-MS analysis.

BACKGROUND: Inflammatory bowel disease (IBD) is a chronic and recurrent inflammatory disorder in gastrointestinal tract. Shen Ling Bai Zhu San (SLBZS), which has a long history of use in Traditional Chinese Medicine (TCM), has been widely used to treat gastrointestinal diseases. The isolated fractions of TCM have also been proved to possess an important potential for treating diseases, which are due to their effective components. PURPOSE: In this study, we examined the possibility that SLBZS and its isolated active fractions may prevent DSS-induced colitis, and investigated the potential mechanisms by regulating genetic profile of colon. METHODS: Colitis mice were induced by 2.5% DSS for 7 days, and then SLBZS and different SLBZS extracts were administrated to protect the mice for 7 days. Body weight, diarrhea, bleeding in stool, colon length, spleen weight, cytokines of serum and colon and pathology of colon were assessed. The level of Ginsenoside Rg1, Re and Rb1 in different SLBZS extracts and qualitative analysis of n-butanol extract of SLBZS (S-Nb) was performed by HPLC and LC-MS, respectively. And the effects of S-Nb on the transcriptome in colitis were investigated. RESULTS: Our results showed that SLBZS and S-Nb significantly regained body weight, reduced DAI, splenomegaly and the length of colon and attenuated histological damage of the colon. Meanwhile, SLBZS and S-Nb markedly reduced the levels of TNF-α, IL-1ß and IL-6 and increased the level of IL-10 in serum and colon. These effects may be associated with the high levels of Ginsenoside Rg1, Re and Rb1 and rich variety of compounds in S-Nb including 6 ginsenosides, glycyrrhizin, L-tryptophan, and so on. Transcriptome analysis revealed that S-Nb selectively regulated 103 differentially expressed genes (DEGs), 36 of which were changed in DSS-induced mice. And the genes of Per2, Per3, Npy and Serpina3m were closely related to colitis and also restored by S-Nb with different extent. Remarkably, these DEGs modulated the biological functions of colitis mice, including extracellular region, response to external stimulus, MAPK signaling pathway and arginine and proline metabolism. CONCLUSIONS: These data indicated that SLBZS and S-Nb blunted DSS-induced colitis by modulating differentially expression gene profile and biological functions based on their ginsenosides and rich compounds.

Polysaccharides derived from Shenling Baizhu San improve colitis via modulating tryptophan metabolism in mice.

Shenling Baizhu San has beneficial effects on the metabolism of the gut microbiota, however, the mechanisms underlying microbiota metabolites mediated anti-inflammation signaling are not well understood. Previously, we have demonstrated that supplementation with Shenling Baizhu San alleviated antibiotic-associated diarrhea (AAD). The current study intends to investigate the dynamic modulation of Shenling Baizhu San polysaccharides (SP) on colitis from the gut microbiota metabolites perspective. Administration of SP effectively relieved colitis induced by DSS in mice, including alleviating body weight loss, the downregulation of colon proinflammatory mediators, and the promotion of intestinal injury repair. Whereas, the efficacy was eliminated by antibiotics, which demonstrated that the efficacy of SP was dependent on the gut microbiota. Fecal microbiota transplantation (FMT) showed that the efficacy of SP can be transferred to gut microbiota. Serum metabolomics analysis showed that supplementation with SP significantly promoted tryptophan metabolism, which was consistent with the changed structure of the gut microbiota, including Bacteroides, Bifidobacterium and Ruminococcus regulated by SP. Especially, the tryptophan metabolites-kynurenine (KYN) activated the expression of amplifying aryl-hydrocarbon receptor (AhR) and Cyp1A1 to promote IL-10 expression in colon. These data suggested that SP positively affected colitis in mice by regulating tryptophan metabolic function of their gut microbiota.

Application of N-methyl-D-aspartate receptor nanopore in screening ligand molecules.

N-methyl-D-aspartate receptors (NMDARs) are crucial for excitatory synaptic transmission in the central nervous system. To study NMDARs more accurately and conveniently, we developed a stable NMDAR nanopore in a planar lipid bilayer. Pharmacological properties were validated using the allosteric modulator Ro 25-6981 and antagonist D-2-amino-5-phosphonopentanoic acid (D-APV). The cyanotoxin ß-N-methylamino-L-alanine (BMAA) found in fresh water systems is suspected to be associated with the development of neurodegenerative diseases. Therefore, BMAA and its two isomers L-2, 4-Diaminobutyric acid dihydrochloride (DAB) and N-(2-aminoethyl) glycine (AEG) and an endogenous excitotoxin, quinolinic acid (QA), were studied using the NMDAR nanopores to assess their effects on NMDAR modulation. We demonstrated that the NMDAR nanopore could reliably detect its ligand molecules at the single-channel level. The study also demonstrated the practicability of NMDAR nanopores, and results were validated using two-electrode voltage-clamp (TEVC) recording. Compared with TEVC recording, the NMDAR nanopores conducted ion channel gating at the single-channel level without being affected by other proteins on the cell membrane. The highly sensitive and accurate NMDAR nanopore technique thus has a unique advantage in screening NMDAR ligand molecules that could be associated with neurodegenerative disease.