Jiang-Tang-San-Huang pill alleviates type 2 diabetes mellitus through modulating the gut microbiota and bile acids metabolism.

Jiang-Tang-San-Huang (JTSH) pill, a traditional Chinese medicine (TCM) prescription, has long been applied to clinically treat type 2 diabetes mellitus (T2DM), while the underlying antidiabetic mechanism remains unclarified. Currently, it is believed that the interaction between intestinal microbiota and bile acids (BAs) metabolism mediates host metabolism and promotes T2DM. To elucidate the underlying mechanisms of JTSH for treating T2DM with animal models. In this study, male SD rats received high-fat diet (HFD) and streptozotocin (STZ) injection to induce T2DM and were treated with different dosages (0.27, 0.54 and 1.08 g/kg) of JTSH pill for 4 weeks; metformin was given as a positive control. Alterations of gut microbiota and BA profiles in the distal ileum were assessed by 16S ribosomal RNA gene sequencing and ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), respectively. Additionally, we conducted quantitative Real Time-PCR and western blotting to determine the mRNA and protein expression levels of intestinal farnesoid X receptor (FXR), fibroblast growth factor 15 (FGF15), Takeda G-protein-coupled receptor 5 (TGR5) and glucagon-like peptide 1 (GLP-1) as well as hepatic cytochrome P450, family 7, subfamily a, poly-peptide 1 (CYP7A1) and cytochrome P450, family 8, subfamily b, poly-peptide 1 (CYP8B1), which are involved in BAs metabolism and enterohepatic circulation. Here, the results revealed that JTSH treatment significantly ameliorated hyperglycaemia, insulin resistance (IR), hyperlipidaemia, and pathological changes in the pancreas, liver, kidney and intestine and reduced the serum levels of pro-inflammatory cytokines in T2DM model rats. 16S rRNA sequencing and UPLC-MS/MS showed that JTSH treatment could modulate gut microbiota dysbiosis by preferentially increasing bacteria (e.g., Bacteroides, Lactobacillus, Bifidobacterium) with bile-salt hydrolase (BSH) activity, which might in turn lead to the accumulation of ileal unconjugated BAs (e.g., CDCA, DCA) and further upregulate the intestinal FXR/FGF15 and TGR5/GLP-1 signaling pathways. The study demonstrated that JTSH treatment could alleviate T2DM by modulating the interaction between gut microbiota and BAs metabolism. These findings suggest that JTSH pill may serve as a promising oral therapeutic agent for T2DM.

Tawulie D ，Jin L ，Shang X ，Li Y ，Sun L ，Xie H ，Zhao J ，Liao J ，Zhu Z ，Cui H ，Wen W ... -  《-》

Amelioration of hyperglycaemia and hyperlipidaemia by adjusting the interplay between gut microbiota and bile acid metabolism: Radix Scutellariae as a case.

Our previous clinical research showed that the interaction between gut microbiota and bile acids (BAs) in patients with type 2 diabetes mellitus (T2DM) changed significantly. We hypothesized that T2DM could be improved by adjusting this interaction mediated by farnesoid X receptor (FXR). T2DM belongs to the category of "xiaoke" in traditional Chinese medicine. Radix scutellariae has the effects of clearing away heat and eliminating dampness, curing jaundice and quenching thirst and is widely used alone or in combination with other medicines for the treatment of T2DM in China and throughout Asia. Additionally, the interaction between Radix scutellariae and gut microbiota may influence its efficacy in the treatment of T2DM. This study chose Radix scutellariae to validate that T2DM could improve by adjusting the interaction between gut microbiota and bile acid metabolism. Radix scutellariae water extract (WESB) was administered to a T2DM rat model established by a high-fat diet combined with streptozotocin. The body weight and blood glucose and insulin levels were measured. The levels of serum lipids, creatinine, uric acid, albumin and total bile acid were also detected. Changes in the pathology and histology of the pancreas, liver and kidney were observed by haematoxylin-eosin staining. The 16S rRNAs of gut microbiota were sequenced, and the faecal and serum BAs were determined by liquid chromatography tandem mass spectrometry. The expression levels of BA metabolism-associated proteins in the liver and intestine were evaluated by immunoblot analysis. The results showed that WESB improved hyperglycaemia, hyperlipaemia, and liver and kidney damage in T2DM rats. In addition, the abundances of key gut microbiota and the concentrations of certain secondary BAs in faeces and serum were restored. Moreover, there was a significant correlation between the restored gut microbiota and BAs, which might be related to the activation of liver cholesterol 7α-hydroxylase (CYP7A1) and the inhibition of FXR expression in the intestine rather than the liver. This study provided new ideas for the prevention or treatment of clinical diabetes and its complications by adjusting the interaction between gut microbiota and bile acid metabolism.

Zhao L ，Ma P ，Peng Y ，Wang M ，Peng C ，Zhang Y ，Li X ... -  《-》

Ji-Ni-De-Xie ameliorates type 2 diabetes mellitus by modulating the bile acids metabolism and FXR/FGF15 signaling pathway.

Introduction: Ji-Ni-De-Xie (JNDX) is a traditional herbal preparation in China. It is widely used to treat type 2 diabetes mellitus (T2DM) in traditional Tibetan medicine system. However, its antidiabetic mechanisms have not been elucidated. The aim of this study is to elucidate the underlying mechanism of JNDX on bile acids (BAs) metabolism and FXR/FGF15 signaling pathway in T2DM rats. Methods: High-performance liquid chromatography-triple quadrupole mass spectrometry (HPLC-QQQ-MS) and UPLC-Q-Exactive Orbitrap MS technology were used to identify the constituents in JNDX. High-fat diet (HFD) combined with streptozotocin (45 mg∙kg-1) (STZ) was used to establish a T2DM rat model, and the levels of fasting blood-glucose (FBG), glycosylated serum protein (GSP), homeostasis model assessment of insulin resistance (HOMA-IR), LPS, TNF-α, IL-1β, IL-6, TG, TC, LDL-C, HDL-C, and insulin sensitivity index (ISI) were measured to evaluate the anti-diabetic activity of JNDX. In addition, metagenomic analysis was performed to detect changes in gut microbiota. The metabolic profile of BAs was analyzed by HPLC-QQQ-MS. Moreover, the protein and mRNA expressions of FXR and FGF15 in the colon and the protein expressions of FGF15 and CYP7A1 in the liver of T2DM rats were measured by western blot and RT-qPCR. Results: A total of 12 constituents were identified by HPLC-QQQ-MS in JNDX. Furthermore, 45 chemical components in serum were identified from JNDX via UPLC-Q-Exactive Orbitrap MS technology, including 22 prototype components and 23 metabolites. Using a T2DM rat model, we found that JNDX (0.083, 0.165 and 0.33 g/kg) reduced the levels of FBG, GSP, HOMA-IR, LPS, TNF-α, IL-1β, IL-6, TG, TC, and LDL-C, and increased ISI and HDL-C levels in T2DM rats. Metagenomic results demonstrated that JNDX treatment effectively improved gut microbiota dysbiosis, including altering some bacteria (e.g., Streptococcus and Bacteroides) associated with BAs metabolism. Additionally, JNDX improved BAs disorder in T2DM rats, especially significantly increasing cholic acid (CA) levels and decreasing ursodeoxycholic acid (UDCA) levels. Moreover, the protein and mRNA expressions of FXR and FGF15 of T2DM rats were significantly increased, while the expression of CYP7A1 protein in the liver was markedly inhibited by JNDX. Discussion: JNDX can effectively improve insulin resistance, hyperglycemia, hyperlipidemia, and inflammation in T2DM rats. The mechanism is related to its regulation of BAs metabolism and activation of FXR/FGF15 signaling pathway.

Tao Y ，Peng F ，Wang L ，Sun J ，Ding Y ，Xiong S ，Tenzin U ，MiMa ，Nhamdriel T ，Fan G ... -  《Frontiers in Pharmacology》

Ablation of gut microbiota alleviates obesity-induced hepatic steatosis and glucose intolerance by modulating bile acid metabolism in hamsters.

Sun L ，Pang Y ，Wang X ，Wu Q ，Liu H ，Liu B ，Liu G ，Ye M ，Kong W ，Jiang C ... -  《-》

Penthorum chinense Pursh. extract attenuates non-alcholic fatty liver disease by regulating gut microbiota and bile acid metabolism in mice.

Penthorum chinense Pursh. (PCP) is commonly used as a Miao ethnomedicine and health food for liver protection in China. Gansukeli (WS3-B-2526-97) is made from the extract of PCP (PCPE) for the treatment of viral hepatitis. In recent years, PCPE has been reported in the treatment of non-alcoholic fatty liver disease (NAFLD), however its potential mechanism is not fully elucidated. To investigate the ameliorating effect of PCPE on high-fat diet (HFD)-induced NAFLD mice and demonstrate whether its protective effect is gut microbiota dependent and associated with bile acid (BA) metabolism. The alleviating effect of PCPE on NAFLD was conducted on male C57BL/6J mice fed an HFD for 16 weeks, and this effect associated with gut microbiota dependent was demonstrated by pseudo-germfree mice treated with antibiotics and fecal microbiota transplantation (FMT). The composition of the gut microbiota in the cecum contents was analyzed by 16S rRNA sequencing, and the levels of BAs in liver and fecal samples were determined by UPLC/MS-MS. The results showed that administration of PCPE for 8 weeks could potently ameliorate HFD-induced NAFLD and alleviate dyslipidemia and insulin resistance. Moreover, PCPE treatment alleviated gut dysbiosis, especially reducing the relative abundance of bile salt hydrolase (BSH)-producing bacteria. Furthermore, PCPE significantly increased the levels of taurine-conjugated BAs in feces, such as tauro-β-muricholic acid (T-βMCA), tauroursodesoxycholic acid (TUDCA), and taurochenodeoxycholic acid (TCDCA), and increased hepatic chenodeoxycholic acid (CDCA). The protein and mRNA expression of farnesoid X receptor (FXR) and fibroblast growth factor 15 (FGF15) were decreased in intestine, increased taurine-conjugated BAs inhibited the intestinal signaling pathway, which was associated with increased genes expression of enzymes in the alternative BA synthesis pathway that reduced the levels of cholesterol. The increased CDCA produced via the alternative BA synthesis pathway promoted hepatic FXR activation and BA excretion. Our study is the first time to demonstrate that PCPE could ameliorate NAFLD in HFD-induced mice by regulating the gut microbiota and BA metabolism, and from a novel perspective, to clarify the mechanism of PCPE in NAFLD.

Li X ，Zhao W ，Xiao M ，Yu L ，Chen Q ，Hu X ，Zhao Y ，Xiong L ，Chen X ，Wang X ，Ba Y ，Guo Q ，Wu X ... -  《-》