Gegen-Qinlian decoction alleviates metabolic dysfunction-associated steatohepatitis by modulating the microbiota-bile acid axis in mice.

Metabolic dysfunction-associated steatohepatitis (MASH) is the progressive form of metabolic dysfunction-associated steatotic liver disease (MASLD), and is currently the most prevalent chronic liver disease worldwide. Gegen-Qinlian decoction (GQD), a classical Traditional Chinese Medicine (TCM) formula from Treatise on Febrile Diseases, has been historically used to treat heat-dampness syndromes. Recent studies revealed that GQD is effective in treating MASH, but the underlying mechanisms remain unknown. This study aims to evaluate the therapeutic effect of GQD on MASH and explore the potential mechanisms targeting the gut microbiota-bile acid (BA) axis. Phytochemical profiling of GQD was performed using UPLC-Q-TOF-MS. MASH was induced in mice via a fructose-, palmitate-, and cholesterol-enriched (FPC) diet, followed by treatment with low-, medium-, or high-dose GQD. H&E and oil red O staining were utilized to examine the histological change, and serum lipids and enzymes were biochemically analyzed. 16SrDNA sequencing was applied to analyze the alteration of the gut microbiota, and the gas chromatography-mass spectrometry technique was introduced to investigate the fecal bile acid (BA) profile. Serum lipopolysaccharide (LPS) concentrations were analyzed by enzyme-linked immunosorbent assay. Intestinal tight junction proteins (ZO1, Occludin) and BA receptors (FXR, TGR5, and VDR) were detected by Western blot and immunofluorescence staining. The quality of GQD was confirmed, and GQD treatment improved hepatic steatosis, reduced the content of liver triglyceride (20-40 % reduction, p < 0.01) and cholesterol (20-25 % reduction, p < 0.01) in FPC-induced MASH mice. High-dose GQD further decreased serum TC (3.97 ± 1.00 vs 5.51 ± 1.11, p < 0.05), LDL-c (0.53 ± 0.18 vs 1.07 ± 0.28, p < 0.01), ALT (31.90 ± 6.20 vs 47.90 ± 12.78, p < 0.05) and ALP (90.83 ± 13.46 vs 132.90 ± 23.67, p < 0.05) levels, suggesting the effects of GQD in counteracting metabolic inflammation. GQD treatment restored gut microbiota diversity and reversed gut dysbiosis by decreasing the abundance of pathogenic bacteria, resulting in reduced serum LPS while enhancing intestinal tight junction proteins (ZO1, Occludin). Concurrently, GQD treatment reshaped fecal BA profiles, increased intestinal TGR5/VDR expression, with BA shifts strongly correlating to microbiota changes. GQD alleviated hepatic and metabolic disorders in MASH mice, possibly through reversing gut dysbiosis and modulating BA profile. Targeting the microbiota-BA axis represents a promising pattern for TCM prescriptions in treating MASH.

Shu X ，Cao Y ，Wu Y ，Chen M ，Zhao W ，Ji G ，Zhang L ... -  《-》

Study on the mechanism of modified Gegen Qinlian decoction in regulating the intestinal flora-bile acid-TGR5 axis for the treatment of type 2 diabetes mellitus based on macro genome sequencing and targeted metabonomics integration.

Currently, there are many drugs available for the treatment of type 2 diabetes mellitus (T2DM), but most of them cause various side effects due to the need for long-term use. As a traditional Chinese medicine, Gegen Qinlian Decoction (GQD) has shown good efficacy and low side effects in the treatment of T2DM in both clinical and basic research. Based on relevant traditional Chinese medicine theories, dried ginger is innovatively added the formula of traditional GQD to create a modified GQD. This modification reduces the side effects of traditional GQD while exerting its therapeutic effect on T2DM. Previous studies have found that the modified GQD can regulate endoplasmic reticulum stress in the liver, inhibit hepatic gluconeogenesis, protect pancreatic islet β cells, and control blood sugar levels by inhibiting the FXR/neuronal ceramide signaling pathway. GQD can also regulate the intestinal microbiota to achieve therapeutic and protective effects in various gastrointestinal diseases. However, there is no research exploring whether the modified GQD achieves its therapeutic mechanism for T2DM by regulating the intestinal microbiota. To explore the mechanism of modified GQD in the treatment of T2DM based on multi-omics, focusing on its effect on the "intestinal flora bile acid TGR5'' axis. The T2DM model was established using db/db mice, which were randomly divided into a model group, metformin group, high-dose GQD group, medium-dose GQD group, low-dose GQD group, while m/m mice were used as blank control. The drug intervention lasted for 12 weeks, during which the general conditions, oral glucose tolerance (OGT), blood glucose, and lipid-related indexes were recorded. Additionally, the fasting insulin (FINS), c-peptide, GLP-1 in serum, and cAMP in the ileum were measured by ELISA assay. Furthermore, the composition, abundance, and function of the intestinal microbiota were determined by macro genome sequencing, while bile acid was detected by targeted metabonomics. For histological evaluation, HE staining was used to observe the pathological changes of the ileum and pancreas, and the ultrastructure of the ileum and pancreas was observed by transmission electron microscopy. Apoptosis in the ileum tissue was detected by Tunel staining. Moreover, the mRNA and protein expressions of TGR5, PKA, CREB, PC1/3, GLP-1, and their phosphorylation levels in the ileum were detected by qPCR, immunohistochemistry, and Western blot; The expression of INS in the pancreas was also evaluated using immunohistochemistry. Finally, double immunofluorescence staining was used to detect the co-localization expression of TGR5 and GLP-1, NeuroD1, and GLP-1 in the ileum. The modified GQD was found to significantly reduce blood glucose, improve oral glucose tolerance, and blood lipid levels, as well as alleviate the injury of the ileum and pancreas in T2DM mice. Furthermore, modified GQD was found to effectively regulate intestinal flora, improve bile acid metabolism, activate the TRG5/cAMP/PKA/CREB signal pathway, and stimulate GLP-1 secretion. GQD can regulate the "intestinal flora-bile acid-TGR5" axis and has a therapeutic effect on T2DM in mice.

Liu R ，Wang J ，Zhao Y ，Zhou Q ，Yang X ，Gao Y ，Li Q ，Bai M ，Liu J ，Liang Y ，Zhu X ... -  《-》

Gegen Qinlian decoction ameliorates TNBS-induced ulcerative colitis by regulating Th2/Th1 and Tregs/Th17 cells balance, inhibiting NLRP3 inflammasome activation and reshaping gut microbiota.

Chinese herbal medicine Gegen Qinlian Decoction (GQD) has been clinically shown to be an effective treatment of ulcerative colitis (UC) in China. However, the underlying mechanism of GQD's anti-ulcerative colitis properties and its effect on gut microbiota still deserve further exploration. This study observed the regulatory effects of GQD on Th2/Th1 and Tregs/Th17 cells balance, the NOD-like receptor family pyrin domain containing 3 (NLRP3) infammasome and gut microbiota in TNBS-induced UC in BALB/c mice. 61 main chemical compounds in the GQD were determined by UPLC-Q-TOF/MS. The UC BALB/c model was established by intrarectal administration of trinitrobenzene sulfonic acid (TNBS), and GQD was orally administered at low and high dosages of 2.96 and 11.83 g/kg/day, respectively. The anti-inflammatory effects of GQD for ulcerative colitis were evaluated by survival rate, body weight, disease activity index (DAI) score, colonic weight and index, spleen index, hematoxylin-eosin (HE) staining and histopathological scores. Flow cytometry was used to detect the percentage of CD4, Th1, Th2, Th17 and Tregs cells. The levels of Th1-/Th2-/Th17-/Tregs-related inflammatory cytokines and additional proinflammatory cytokines (IL-1β, IL-18) were detected by CBA, ELISA, and RT-PCR. The expressions of GATA3, T-bet, NLRP3, Caspase-1, IL-Iβ, Occludin and Zonula occludens-1 (ZO-1) on colon tissues were detected by Western blot and RT-PCR. Transcriptome sequencing was performed using colon tissue and 16S rRNA gene sequencing was performed on intestinal contents. Fecal microbiota transplantation (FMT) was employed to assess the contribution of intestinal microbiota and its correlation with CD4 T cells and the NLRP3 inflammasome. GQD increased the survival rate of TNBS-induced UC in BALB/c mice, and significantly improved their body weight, DAI score, colonic weight and index, spleen index, and histological characteristics. The intestinal barrier dysfunction was repaired after GQD administration through promoting the expression of tight junction proteins (Occludin and ZO-1). GQD restored the balance of Th2/Th1 and Tregs/Th17 cells immune response of colitis mice, primarily inhibiting the increase in Th2/Th1 ratio and their transcription factor production (GATA3 and T-bet). Morever, GQD changed the secretion of Th1-/Th2-/Th17-/Tregs-related cytokines (IL-2, IL-12, IL-5, IL-13, IL-6, IL-10, and IL-17A) and reduced the expressions of IL-1β, IL-18. Transcriptome results suggested that GQD could also remodel the immune inflammatory response of colitis by inhibiting NOD-like receptor signaling pathway, and Western blot, immunohistochemistry and RT-PCR further revealed that GQD exerted anti-inflammatory effects by inhibiting the NLRP3 inflammasome, such as down-regulating the expression of NLRP3, Caspase-1 and IL-1β. More interestingly, GQD regulated gut microbiota dysbiosis, suppressed the overgrowth of conditional pathogenic gut bacteria like Helicobacter, Proteobacteria, and Mucispirillum, while the probiotic gut microbiota, such as Lactobacillus, Muribaculaceae, Ruminiclostridium_6, Akkermansia, and Ruminococcaceae_unclassified were increased. We further confirmed that GQD-treated gut microbiota was sufficient to relieve TNBS-induced colitis by FMT, involving the modulation of Th2/Th1 and Tregs/Th17 balance, inhibition of NLRP3 inflammasome activation, and enhancement of colonic barrier function. GQD might alleviate TNBS-induced UC via regulating Th2/Th1 and Tregs/Th17 cells Balance, inhibiting NLRP3 inflammasome and reshaping gut microbiota, which may provide a novel strategy for patients with colitis.

Hu Y ，Tang J ，Xie Y ，Xu W ，Zhu W ，Xia L ，Fang J ，Yu D ，Liu J ，Zheng Z ，Zhou Q ，Shou Q ，Zhang W ... -  《-》

Gegen Qinlian decoction activates AhR/IL-22 to repair intestinal barrier by modulating gut microbiota-related tryptophan metabolism in ulcerative colitis mice.

Gegen Qinlian decoction (GQD) is a traditional Chinese medicine derived from Treatise on febrile diseases and is clinically used for the treatment of acute ulcerative colitis (UC). However, the potential mechanism of GQD treatment for UC remains elusive. In this study, we aimed to explore the involvement of gut microbiota-related tryptophan metabolism in mediating protective effects of GQD against intestinal barrier damage. Mice with colitis were treated with 3% dextran sulfate sodium (DSS) for 6 days. The therapeutic effects of GQD in UC mice were examined based on body weight, disease activity index (DAI), organ index, length and pathological changes in the colon. The distribution of fluorescein isothiocyanate dextran (FITC-dextran) in the intestinal tract was observed using small animal imaging, while concentration of FITC-dextran in serum was detected using a fluorescein microplate analyser. Bacterial infiltration in colon tissues was observed by fluorescence in situ hybridisation (FISH), and the bacterial load in mesenteric lymph nodes (MLNs) was further examined through bacterial culture. Subsequently, colonic goblet cells were detected using Alcian blue staining. The tight junctions of the colonic epithelium were observed using transmission electron microscopy, and the expression of tight junction proteins was detected by immunofluorescence (IF) and western blot. In addition, flow cytometry was used to analyse the proportion of interleukin-22-positive (IL-22+) ILC3 cells in lamina propria lymphocytes, and the content of IL-22 in colon homogenates was determined using an ELISA kit. In addition, targeted tryptophan metabolomics was used to detect the concentration of indole derivatives produced by tryptophan metabolism in faeces, and 16S rDNA was used to investigate the composition and abundance of gut microbiota-related tryptophan metabolism. Administration of GQD significantly alleviated the pathological symptoms, including weight loss, increased DAI score, changes in organ index, colon shortening, and colon pathological injury in UC mice. In addition, GQD reduced the diffusion of FITC-dextran in the intestinal tract, the content of FITC-dextran in serum, and bacterial infiltration in MLNs and colon tissues. Additionally, GQD significantly increased the number of colonic goblet cells, repaired the structure of epithelial tight junctions and increased the expression of tight junction proteins. Furthermore, GQD significantly increased the proportion of IL-22+ ILC3 in the lamina propria, the expression of CYP1A1 protein in colon tissue, and the level of IL-22 in colon homogenates. However, the above protective effects of GQD were inhibited by co-administration of GQD and aryl hydrocarbon receptor (AhR) antagonist. Additionally, GQD restored the content of indole derivatives generated by tryptophan metabolism, regulated the diversity of the gut microbiota, and significantly increased the abundance of genes related to tryptophan metabolism. Our results confirmed that GQD repaired the damaged intestinal barrier in UC mice by regulating gut microbiota-related tryptophan metabolism and restoring the generation of indole derivatives to activate AhR-mediated IL-22 production.

Wang X ，Huang S ，Zhang M ，Su Y ，Pan Z ，Liang J ，Xie X ，Wang Q ，Chen J ，Zhou L ，Luo X ... -  《-》

Tetrahydrocurcumin Alleviates Metabolic Dysfunction-Associated Steatohepatitis in Mice by Regulating Serum Lipids, Bile Acids, and Gut Microbiota.

Peng S ，Meng M ，Luo P ，Liu J ，Wang J ，Chen Y ... -  《INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES》