Microbial Fermentation Enhances the Effect of Black Tea on Hyperlipidemia by Mediating Bile Acid Metabolism and Remodeling Intestinal Microbes.

Black tea (BT), the most consumed tea worldwide, can alleviate hyperlipidemia which is a serious threat to human health. However, the quality of summer BT is poor. It was improved by microbial fermentation in a previous study, but whether it affects hypolipidemic activity is unknown. Therefore, we compared the hypolipidemic activity of BT and microbially fermented black tea (EFT). The results demonstrated that BT inhibited weight gain and improved lipid and total bile acid (TBA) levels, and microbial fermentation reinforced this activity. Mechanistically, both BT and EFT mediate bile acid circulation to relieve hyperlipidemia. In addition, BT and EFT improve dyslipidemia by modifying the gut microbiota. Specifically, the increase in Lactobacillus johnsonii by BT, and the increase in Mucispirillum and Colidextribacter by EFT may also be potential causes for alleviation of hyperlipidemia. In summary, we demonstrated that microbial fermentation strengthened the hypolipidemic activity of BT and increased the added value of BT.

Zearalenone Decreases Food Intake by Disrupting the Gut-Liver-Hypothalamus Axis Signaling via Bile Acids.

Zearalenone (ZEN) is a mycotoxin that is harmful to humans and animals. In this study, female and male rats were exposed to ZEN, and the results showed that ZEN reduced the farnesoid X receptor (FXR) expression levels in the liver and disrupted the enterohepatic circulation of bile acids (BAs). A decrease in food intake induced by ZEN was negatively correlated with an increase in the level of total BAs. BA-targeted metabolomics revealed that ZEN increased glycochenodeoxycholic acid levels and decreased the ratio of conjugated BAs to unconjugated BAs, which further increased the hypothalamic FXR expression levels. Preventing the increase in total BA levels induced by ZEN via Lactobacillus rhamnosus GG intervention restored the appetite. In conclusion, ZEN disrupted the enterohepatic circulation of BAs to decrease the level of food intake. This study reveals a possible mechanism by which ZEN affects food intake and provides a new approach to decrease the toxic effects of ZEN.

Mechanistic studies on the alleviation of ANIT-induced cholestatic liver injury by Polygala fallax Hemsl. polysaccharides.

ETHNOPHARMACOLOGICAL RELEVANCE: Polygala fallax Hemsl. is a traditional folk medicine commonly used by ethnic minorities in the Guangxi Zhuang Autonomous Region, and has a traditional application in the treatment of liver disease. Polygala fallax Hemsl. polysaccharides (PFPs) are of interest for their potential health benefits. AIM OF THIS STUDY: This study explored the impact of PFPs on a mouse model of cholestatic liver injury (CLI) induced by alpha-naphthyl isothiocyanate (ANIT), as well as the potential mechanisms. MATERIALS AND METHODS: A mouse CLI model was constructed using ANIT (80 mg/kg) and intervened with different doses of PFPs or ursodeoxycholic acid. Their serum biochemical indices, hepatic oxidative stress indices, and hepatic pathological characteristics were investigated. Then RNA sequencing was performed on liver tissues to identify differentially expressed genes and signaling pathways and to elucidate the mechanism of liver protection by PFPs. Finally, Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blotting were used to verify the differentially expressed genes. RESULTS: Data analyses showed that PFPs reduced the levels of liver function-related biochemical indices, such as ALT, AST, AKP, TBA, DBIL, and TBIL. PFPs up-regulated the activities of SOD and GSH, down-regulated the contents of MDA, inhibited the release of IL-1ß, IL-6, and TNF-α, or promoted IL-10. Pathologic characterization of the liver revealed that PFPs reduced hepatocyte apoptosis or necrosis. The RNA sequencing indicated that the genes with differential expression were primarily enriched for the biosynthesis of primary bile acids, secretion or transportation of bile, the reactive oxygen species in chemical carcinogenesis, and the NF-kappa B signaling pathway. In addition, the results of qRT-PCR and Western blotting analysis were consistent with those of RNA sequencing analysis. CONCLUSIONS: In summary, this study showed that PFPs improved intrahepatic cholestasis and alleviated liver damage through the modulation of primary bile acid production, Control of protein expression related to bile secretion or transportation, decrease in inflammatory reactions, and inhibition of oxidative pressure. As a result, PFPs might offer a hopeful ethnic dietary approach for managing intrahepatic cholestasis.

Dan-shen Yin promotes bile acid metabolism and excretion to prevent atherosclerosis via activating FXR/BSEP signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Dan-shen Yin (DSY), a traditional prescription, has been demonstrated to be effective in decreasing hyperlipidemia and preventing atherosclerosis (AS), but its mechanism remains unknown. We hypothesized that DSY activates farnesoid X receptor (FXR) to promote bile acid metabolism and excretion, thereby alleviating AS. AIM OF THE STUDY: This study was designed to explore whether DSY reduces liver lipid accumulation and prevents AS by activating FXR and increasing cholesterol metabolism and bile acid excretion. MATERIALS AND METHODS: The comprehensive chemical characterization of DSY was analyzed by UHPLC-MS/MS. The AS models of ApoE-/- mice and SD rats was established by high-fat diet and high-fat diet combined with intraperitoneal injection of vitamin D3, respectively. The aortic plaque and pathological changes were used to evaluate AS. Lipid levels, H&E staining and oil red O staining were used to evaluate liver lipid accumulation. The cholesterol metabolism and bile acid excretion were evaluated by enzyme-linked immunosorbent assay, UPLC-QQQ/MS. In vitro, the lipid and FXR/bile salt export pump (BSEP) levels were evaluated by oil red O staining, real-time quantitative polymerase chain reaction (RT-qPCR) and western blotting. RESULTS: A total of 36 ingredients in DSY were identified by UPLC-MS/MS analysis. In vivo, high-dose DSY significantly inhibited aortic intimal thickening, improved arrangement disorder, tortuosity, and rupture of elastic fibers, decreased lipid levels, and reduced the number of fat vacuoles and lipid droplets in liver tissue in SD rats and ApoE-/- mice. Further studies found that high-dose DSY significantly reduced liver lipid and total bile acids levels, increased liver ursodeoxycholic acid (UDCA) and other non-conjugated bile acids levels, increased fecal total cholesterol (TC) levels, and augmented FXR, BSEP, cholesterol 7-alpha hydroxylase (CYP7A1), ATP binding cassette subfamily G5/G8 (ABCG5/8) expression levels, while decreasing ASBT expression levels. In vitro studies showed that DSY significantly reduced TC and TG levels, as well as lipid droplets, while also increasing the expression of ABCG5/8, FXR, and BSEP in both HepG2 and Nr1h4 knockdown HepG2 cells. CONCLUSION: This study demonstrated that DSY promotes bile acid metabolism and excretion to prevent AS by activating FXR. For the prevent of AS and drug discovery provided experimental basis.

Metabolomic profiling of serum and tongue coating of pregnant women with intrahepatic cholestasis in pregnancy.

Intrahepatic cholestasis of pregnancy (ICP) is associated with an increased risk of cesarean section and adverse fetal outcomes. Currently, ICP diagnosis depends largely on serum levels of bile acids and lacks sensitivity and specificity for accurate diagnosis. Tongue diagnosis is an important diagnostic tool in traditional Chinese medicine (TCM) and is used in our clinic as complementary treatment and personalized medicine for ICP. However, the molecular basis of the manifestation of greasy white tongue coatings in ICP remains unknown. In this study, we performed untargeted metabolomic profiling of the serum, tongue coating, and saliva of 66 pregnant women, including 22 with ICP. The metabolomic profiles of the serum and tongue coatings showed marked differences between the two clinical groups. Forty-six differentially abundant metabolites were identified, and their relative concentrations correlated with total bile acid levels. These differential metabolites included bile acids, lipids, microbiota- and diet-related metabolites, and exposomes. Conventional biochemical markers, including serum aminotransferases and bilirubin, were not significantly increased in the ICP group, whereas the total cholesterol and triglyceride levels were significantly increased as early as the first trimester. Our data provide insights into the pathophysiology of ICP and implicate the gut-liver axis and environmental exposure. Tongue coating has the potential to be a non-invasive diagnostic approach. Further studies are required to validate the clinical utility of these findings.

Mechanism of Tianma-Gouteng granules lowering blood pressure based on the bile acid-regulated Farnesoid X Receptor-Fibroblast Growth Factor 15- Cholesterol 7α-hydroxylase pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Tianma-Gouteng granules (TGG) is a traditional Chinese medicine (TCM) compound that was first recorded by modern medical practitioner Hu Guangci in "New Meaning of the Treatment of Miscellaneous Diseases in Traditional Chinese Medicine". It is widely used to treat hypertensive vertigo, headache and insomnia. AIM OF STUDY: To investigate the antihypertensive effect of TGG and explore its mechanism. MATERIALS AND METHODS: Spontaneously hypertensive rats (SHR) were prepared a model of the ascendant hyperactivity of liver yang syndrome (AHLYS), blood pressure and general state of rats were recorded. A series of experiments were performed by enzyme-linked immunosorbent assay (ELISA), ultra high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-QTOF-MS), 16S rRNA sequencing, real-time fluorescence quantitative PCR (RT-qPCR), and enzymatic colorimetry. RESULTS: TGG can effectively lower blood pressure and improve related symptoms. TGG significantly reduced the levels of IL-1ß, IL-6, TNF-α, Renin and AngII. A total of 17 differential metabolites were found in plasma, with the two most potent metabolic pathways being glycerophospholipid metabolism and primary bile acid biosynthesis. After TGG intervention, 7 metabolite levels decreased and 10 metabolite levels increased. TGG significantly increased the relative abundance of Desulfovibio, Lachnoclostridium, Turicibacter, and decreased the relative abundance of Alluobaculum and Monoglobu. TGG also downregulated Farnesoid X Receptor (FXR) and Fibroblast Growth Factor 15 (FGF15) levels in the liver and ileum, upregulated Cholesterol 7α-hydroxylase (CYP7A1) levels, and regulated total bile acid (TBA) levels. CONCLUSION: TGG can regulate bile acid metabolism through liver-gut axis, interfere with related intestinal flora and plasma metabolites, decrease blood pressure, and positively influence the pathologic process of SHR with AHLYS. When translating animal microbiota findings to humans, validation studies are essential to confirm reliability and applicability, particularly through empirical human research.

Gehua Jiejiu Dizhi decoction ameliorates alcoholic fatty liver in mice by regulating lipid and bile acid metabolism and with exertion of antioxidant stress based on 4DLabel-free quantitative proteomic study.

OBJECTIVE: To analyze the effect and molecular mechanism of Gehua Jiejiu Dizhi decoction (, GJDD) on alcoholic fatty live disease (AFLD) by using proteomic methods. METHODS: The male C57BL/6J mouse were randomly divided into four groups: control group, model group, GJDD group and resveratrol group. After the AFLD model was successfully prepared by intragastric administration of alcohol once on the basis of the Lieber-DeCarli classical method, the GJDD group and resveratrol group were intragastrically administered with GJDD (4900 mg/kg) and resveratrol (400 mg/kg) respectively, once a day for 9 d. The fat deposition of liver tissue was observed and evaluated by oil red O (ORO) staining. 4DLabel-free quantitative proteome method was used to determine and quantify the protein expression in liver tissue of each experimental group. The differentially expressed proteins were screened according to protein expression differential multiples, and then analyzed by Gene ontology classification and Kyoto Encyclopedia of Genes and Genomes pathway enrichment. Finally, expression validation of the differentially co-expressed proteins from control group, model group and GJDD group were verified by targeted proteomics quantification techniques. RESULTS: In semiquantitative analyses of ORO, all kinds of steatosis (ToS, MaS, and MiS) were evaluated higher in AFLD mice compared to those in GJDD or resveratrol-treated mice. 4DLabel-free proteomics analysis results showed that a total of 4513 proteins were identified, of which 3763 proteins were quantified and 946 differentially expressed proteins were screened. Compared with the control group, 145 proteins were up-regulated and 148 proteins were down-regulated in the liver tissue of model group. In addition, compared with the model group, 92 proteins were up-regulated and 135 proteins were down-regulated in the liver tissue of the GJDD group. 15 differentially co-expressed proteins were found between every two groups (model group vs control group, GJDD group vs model group and GJDD group vs control group), which were involved in many biological processes. Among them, 11 differentially co-expressed key proteins (Aox3, H1-5, Fabp5, Ces3a, Nudt7, Serpinb1a, Fkbp11, Rpl22l1, Keg1, Acss2 and Slco1a1) were further identified by targeted proteomic quantitative technology and their expression patterns were consistent with the results of 4D label-free proteomic analysis. CONCLUSIONS: Our study provided proteomics-based evidence that GJDD alleviated AFLD by modulating liver protein expression, likely through the modulation of lipid metabolism, bile acid metabolism and with exertion of antioxidant stress.

Artemisia capillaris Thunb. Polysaccharide alleviates cholestatic liver injury through gut microbiota modulation and Nrf2 signaling pathway activation in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: According to traditional Chinese medicine (TCM) theory, cholestasis belongs to category of jaundice. Artemisia capillaris Thunb. has been widely used for the treatment of jaundice in TCM. The polysaccharides are the one of main active components of the herb, but its effects on cholestasis remain unclear. AIM OF THE STUDY: To investigate the protective effect and mechanism of Artemisia capillaris Thunb. polysaccharide (APS) on cholestasis and liver injury. MATERIALS AND METHODS: The amelioration of APS on cholestasis was evaluated in an alpha-naphthyl isothiocyanate (ANIT)-induced mice model. Then nuclear Nrf2 knockout mice, mass spectrometry, 16s rDNA sequencing, metabolomics, and molecular biotechnology methods were used to elucidate the associated mechanisms of APS against cholestatic liver injury. RESULTS: Treatment with low and high doses of APS markedly decreased cholestatic liver injury of mice. Mechanistically, APS promoted nuclear translocation of hepatic nuclear factor erythroid 2-related factor (Nrf2), upregulated downstream bile acid (BA) efflux transporters and detoxifying enzymes expression, improved BA homeostasis, and attenuated oxidative liver injury; however, these effects were annulled in Nrf2 knock-out mice. Furthermore, APS ameliorated the microbiota dysbiosis of cholestatic mice and selectively increased short-chain fatty acid (SCFA)-producing bacteria growth. Fecal microbiota transplantation of APS also promoted hepatic Nrf2 activation, increased BA efflux transporters and detoxifying enzymes expression, ameliorated intrahepatic BA accumulation and cholestatic liver injury. Non-targeted metabolomics and in vitro microbiota culture confirmed that APS significantly increased the production of a microbiota-derived SCFA (butyric acid), which is also able to upregulate Nrf2 expression. CONCLUSIONS: These findings indicate that APS can ameliorate cholestasis by modulating gut microbiota and activating the Nrf2 pathway, representing a novel therapeutic approach for cholestatic liver disease.

JiaGaSongTang improves chronic cholestasis via enhancing FXR-mediated bile acid metabolism.

BACKGROUND: Bile acid (BA) enterohepatic circulation disorders are a main feature of chronic cholestatic diseases. Promoting BA metabolism is thus a potential method of improving enterohepatic circulation disorders, and treat enterohepatic inflammation, oxidative stress and fibrosis due to cholestasis. PURPOSE: To investigate the effect of JiaGaSongTang (JGST) and its blood-absorbed ingredient 6-gingerol on α-naphthylisothiocyanate (ANIT)-induced chronic cholestasis, as well as elucidate the underlying regulatory mechanism. METHODS: Chronic cholestasis was induced in mice via subcutaneous injection of ANIT (50 mg/kg) every other day for 14 d. Treatment groups were administered JGST orally daily. Damage to the liver and intestine was observed using histopathological techniques. Biochemical techniques were employed to assess total BA (TBA) levels in the serum, liver, and ileum samples. Liquid chromatograph-mass spectrometry/mass spectrometry (LC-MS/MS) was used to analyze fecal BA components. Bioinformatic methods were adopted to screen the core targets and pathways. The blood-absorbed ingredients of JGST were scrutinized via LC-MS/MS. The effects of the major JGST ingredients on farnesoid X receptor (FXR) transactivation were validated using dual luciferase reporter genes. Lastly, the effects of the FXR inhibitor, DY268, on JGST and 6-gingerol pharmacodynamics were observed at the cellular and animal levels. RESULTS: JGST ameliorated pathological impairments in the liver and intestine, diminishing TBA levels in the serum, liver and gut. Fecal BA profiling revealed that JGST enhanced the excretion of toxic BA constituents, including deoxycholic acid. Bioinformatic analyses indicated that JGST engaged in anti-inflammatory mechanisms, attenuating collagen accumulation, and orchestrating BA metabolism via interactions with FXR and other pertinent targets. LC-MS/MS analysis identified six ingredients absorbed to the bloodstream, including 6-gingerol. Surface plasmon resonance (SPR) and dual luciferase reporter gene assays confirmed the abilities of 6-gingerol to bind to FXR and activate its transactivation. Ultimately, in both cellular and animal models, the therapeutic efficacy of JGST and 6-gingerol in chronic cholestasis was attenuated in the presence of FXR inhibitors. CONCLUSION: The findings, for the first time, demonstrated that 6-gingerol, a blood-absorbed ingredient of JGST, can activate FXR to affect BA metabolism, and thereby attenuate ANIT-induced liver and intestinal injury in chronic cholestasis mice model via inhibition of inflammation, oxidative stress, and liver fibrosis, in part in a FXR-dependent mechanism.

Involvement of the vagus nerve and hepatic gene expression in serum adiponectin concentrations in mice

Several humoral factors, such as adiponectin and urate, have been suggested to affect metabolic syndromes. Previously, we reported a reduction in blood adiponectin concentrations after a high-fructose diet partially via the vagus nerve in rats. Although a lithogenic diet (LD), i.e., supplementation of a normal control diet (CT) with 0.6% cholesterol and 0.2% sodium cholate, reduced blood adiponectin concentrations, the involvement of the vagus nerve in this mechanism remains unclear. To estimate the involvement of the vagus nerve in the regulation of blood adiponectin concentrations using an LD, male imprinting control region mice that had been vagotomized (HVx) or only laparotomized (Sham) were administered a CT or an LD for 10 weeks. Serum adiponectin concentrations in the Sham-LD, HVx-CT, and HVx-LD groups were reduced by half compared with the Sham-CT group. The hepatic mRNA levels of fibroblast growth factor 21 (Fgf21), which reportedly stimulates adiponectin secretion from white adipose tissue, were lower in the LD groups compared with the CT groups. HepG2 hepatoma cells showed that various bile acids reduced the mRNA expression of FGF21. Moreover, the LD increased serum urate concentrations and reduced hepatic expressions of the acyl-CoA oxidase 1 (Acox1) mRNA and glucokinase, suggesting insufficient regeneration of ATP from AMP. In conclusion, serum adiponectin concentration may be regulated via the vagus nerve in normal mice, whereas a reduction of hepatic Fgf21 mRNA by bile acids may also lower serum adiponectin levels. Moreover, the LD may promote hepatic AMP accumulation and subsequently increase the serum urate concentration in mice. (AU)

Integrated network pharmacology, metabolomics, and transcriptomics of Huanglian-Hongqu herb pair in non-alcoholic fatty liver disease.

ETHNOPHARMACOLOGICAL RELEVANCE: The Huanglian-Hongqu herb pair (HH) is a synergistic drug combination used to treat non-alcoholic fatty liver disease (NAFLD). However, the molecular mechanism underlying the therapeuticeffects of HH requires further elucidation. AIM OF THE STUDY: The present study explored the potential mechanism of HH in treating NAFLD. MATERIALS AND METHODS: UPLC-Q-TOF-MS was employed to identify the drug constituents in HH. A NAFLD rat model was induced by a high-fat diet (HFD) and treated with different doses of HH. The functional mechanism of HH in NAFLD rats was predicted using network pharmacology, metabolomics and transcriptomics. Immunohistochemistry, real-time PCR, and Western blot were performed to validate the key mechanisms. RESULTS: Pharmacodynamic assessment demonstrated that HH exhibited improvements in lipid deposition and reduced hepatic oxidative stress in NAFLD rats. Hepatic wide-target metabolomics revealed that HH primarily modulated amino acids and their metabolites, fatty acids, organic acids and their derivatives, bile acids, and other liver metabolites. The enriched pathways included metabolic pathways, primary bile acid biosynthesis, and bile secretion. Network pharmacology analysis indicated that HH regulated the key pathways in NAFLD, notably PPAR, AMPK, NF-κB and other signaling pathways. Furthermore, hepatic transcriptomics, based on Illumina RNA-Seq sequencing analyses, suggested that HH improved NAFLD through metabolic pathways, the PPAR signaling pathway, primary bile acid biosynthesis, and fatty acid metabolism. Further mechanistic studies indicated that HH could regulate the genes and proteins associated with the PPAR signaling pathway. CONCLUSION: Our findings demonstrated that the potential therapeutic benefits of HH in ameliorating NAFLD by targeting the PPAR signaling pathway, thereby facilitating a more extensive use of HH in NAFLD.

Integration of pharmacodynamics and metabolomics to reveal rhubarb anthraquinone protection against nonalcoholic fatty liver disease rat model.

OBJECTIVES: The objective of the present study was to investigate the effect of Rhubarb anthraquinone (RA) on a high-fat diet (HFD)-induced nonalcoholic fatty liver disease (NAFLD) rat model, and explore potential biomarker and metabolic pathways by using the metabolomics method. MATERIALS AND METHODS: We established HFD rats as the NAFLD model. Forty Sprague-Dawley rats were randomly divided into a control group, model group, RA low-dose group, RA medium-dose group, and RA high-dose group, and evaluated the protective effect of RA on NAFLD by detecting biochemical indicators of serum and pathological changes of liver tissue. Investigating potential biomarkers and metabolic pathways connected with RA's protective effects against NAFLD by UHPLC-Q-TOF-MS untargeted metabolomics. RESULTS: The results showed that RA significantly reversed the increase of TG, TC, ALT, AST, and ALP (P < .05), the decrease of HDL-C (P < .05), and alleviated pathological conditions in NAFLD rats. Based on potential biomarker analysis, RA affected metabolic pathways such as fatty acids biosynthesis, bile acids biosynthesis, and pentose phosphate pathway, delaying the progression of NAFLD. CONCLUSION: RA improved blood lipid levels, liver function, and pathological conditions of NAFLD rats. Meanwhile, affected the metabolic pathways and regulated the synthesis of fatty acids and bile acids in NAFLD rats.

Statins aggravate insulin resistance through reduced blood glucagon-like peptide-1 levels in a microbiota-dependent manner.

Statins are currently the most common cholesterol-lowering drug, but the underlying mechanism of statin-induced hyperglycemia is unclear. To investigate whether the gut microbiome and its metabolites contribute to statin-associated glucose intolerance, we recruited 30 patients with atorvastatin and 10 controls, followed up for 16 weeks, and found a decreased abundance of the genus Clostridium in feces and altered serum and fecal bile acid profiles among patients with atorvastatin therapy. Animal experiments validated that statin could induce glucose intolerance, and transplantation of Clostridium sp. and supplementation of ursodeoxycholic acid (UDCA) could ameliorate statin-induced glucose intolerance. Furthermore, oral UDCA administration in humans alleviated the glucose intolerance without impairing the lipid-lowering effect. Our study demonstrated that the statin-induced hyperglycemic effect was attributed to the Clostridium sp.-bile acids axis and provided important insights into adjuvant therapy of UDCA to lower the adverse risk of statin therapy.

Salvianolic acid extract prevents Tripterygium wilfordii polyglycosides-induced acute liver injury by modulating bile acid metabolism.

ETHNOPHARMACOLOGICAL RELEVANCE: Tripterygium wilfordii polyglycosides (TWP) tablet is the most widely used traditional Chinese medicine preparation for the treatment of rheumatoid arthritis (RA), but the hepatotoxicity often limits its widespread application. In traditional use, Salvia miltiorrhiza has cardioprotective and hepatoprotective effects. Salvianolic acid extract (SA) is a hydrophilic component of Salvia miltiorrhiza and has significant antioxidant and hepatoprotective effects. AIM OF THE STUDY: To investigate the protective effects of SA on the TWP-induced acute liver injury in rats and to explore the related mechanisms by integration of metabolomics and transcriptomics. MATERIALS AND METHODS: SA and TWP extracts were identified by UPLC-Q/TOF-MS. SA (200 mg/kg) was administered for consecutive 7 days. On day 7, TWP (360 mg/kg) was administered by gavage to induce the acute liver injury in rats. Serum biochemical assay and H&E staining were used to evaluate liver damage. Liver metabolomics and transcriptomics were used to explore the potential mechanisms, and further molecular biological experiments such as qPCR and IHC were utilized to validate the relevant signaling pathways. RESULTS: SA can prevent liver injury symptoms caused by TWP, such as elevated liver index, elevated ALT and AST, and pathological changes in liver tissue. Liver metabolomics studies showed that TWP can significantly alter the content of individual bile acid in the liver and SA had the most significant impact on the biosynthetic pathway of bile acids. The transcriptomics results of the liver indicated that the genes changed in the SA + TWP group were mainly involved in sterol metabolism, lipid regulation and bile acid homeostasis pathways. The gene expression of Nr1h4, which encodes farnesoid X receptor (FXR), an important regulator of bile acid homeostasis, was significantly changed. Further studies confirmed that SA can prevent the downregulation of FXR and its downstream signaling induced by TWP, thereby regulating bile acid metabolism, ultimately preventing acute liver injury caused by TWP. CONCLUSION: Our results demonstrated that SA could protect the liver from TWP-induced hepatic injury by modulation of the bile acid metabolic pathway. SA may provide a new strategy for the protection against TWP-induced acute liver injury.

Ginsenosides retard atherogenesis via remodelling host-microbiome metabolic homeostasis.

BACKGROUND AND PURPOSE: Panax ginseng is widely applied in the adjuvant treatment of cardiometabolic diseases in clinical practice without clear mechanisms. This study aims to clearly define the efficacy and underlying mechanism of P. ginseng and its active components in protecting against atherosclerosis. EXPERIMENTAL APPROACH: The anti-atherogenic efficacy of total ginseng saponin extract (TGS) and its components was evaluated on Ldlr-/- mice. Gut microbial structure was analysed by 16S rRNA sequencing and PCR. Bile acid profiles were revealed using targeted metabolomics with LC-MS/MS analysis. The contribution of gut microbiota to atherosclerosis was assessed by co-housing experiments. KEY RESULTS: Ginsenoside Rb1, representing protopanaxadiol (PPD)-type saponins, increased intestinal Lactobacillus abundance, resulting in enhanced bile salt hydrolase (BSH) activity to promote intestinal conjugated bile acid hydrolysis and excretion, followed by suppression of enterohepatic farnesoid X receptor (FXR)-fibroblast growth factor 15 (FGF15) signal, and thereby increased cholesterol 7α-hydroxylase (CYP7A1) transcriptional expression and facilitated metabolic elimination of cholesterol. Synergistically, protopanaxatriol (PPT)-type saponins, represented by ginsenoside Rg1, protected against atherogenesis-triggered gut leak and metabolic endotoxaemia. Ginsenoside Rg1 directly induced mucin production to nutritionally maintain Akkermansia muciniphila, which reciprocally inhibited gut permeation. Rb1/Rg1 combination, rather than a single compound, can largely mimic the holistic efficacy of TGS in protecting Ldlr-/- mice from atherogenesis. CONCLUSION AND IMPLICATIONS: Our study provides strong evidence supporting TGS and ginsenoside Rb1/Rg1 combinations as effective therapies against atherogenesis, via targeting different signal nodes by different components and may provide some elucidation of the holistic mode of herbal medicines.

Dietary Supplementation with Cholic Acid Reduces Insulin Secretion in Response to Intraperitoneal Glucose Administration in Rats.

The major characteristic of type 2 diabetes is insulin resistance, which is associated with plasma level of 12-hydroxylated bile acids (BAs) in humans. In this study, we investigated whether the rise of enterohepatic 12-hydroxylated BAs associates with glucose tolerance and/or insulin secretion using rats fed a diet supplemented with cholic acid (CA) at a level of 0.5 g/kg diet. Almost no increase was observed in plasma insulin in response to the intraperitoneal glucose administration in the CA-fed rats despite the significant increase of plasma insulin in control with the same treatment. In contrast, the changes in insulin secretion were observed in both groups and no difference was detected between the groups in the oral glucose tolerance test. Increases were observed in pancreatic expressions of Ins1 and Ins2 although the insulin protein content decreased in the pancreas without any sign in ectopic fat accumulation and histological damage in the CA-fed rats. Our results suggest that enterohepatic 12-hydroxylated BAs modulate insulin secretion in response to intraperitoneal glucose administration. The decrease in insulin store might be responsible for the reduction in the insulin secretion in the CA-fed rats.

Multi-omics reveals deoxycholic acid modulates bile acid metabolism via the gut microbiota to antagonize carbon tetrachloride-induced chronic liver injury.

Deoxycholic acid (DCA) serves essential functions in both physiological and pathological liver processes; nevertheless, the relationship among DCA, gut microbiota, and metabolism in chronic liver injury remain insufficiently understood. The primary objective of this study is to elucidate the potential of DCA in ameliorating chronic liver injury and evaluate its regulatory effect on gut microbiota and metabolism via a comprehensive multi-omics approach. Our study found that DCA supplementation caused significant changes in the composition of gut microbiota, which were essential for its antagonistic effect against CCl4-induced chronic liver injury. When gut microbiota was depleted with antibiotics, the observed protective efficacy of DCA against chronic liver injury became noticeably attenuated. Mechanistically, we discovered that DCA regulates the metabolism of bile acids (BAs), including 3-epi DCA, Apo-CA, and its isomers 12-KLCA and 7-KLCA, IHDCA, and DCA, by promoting the growth of A.muciniphila in gut microbiota. This might lead to the inhibition of the IL-17 and TNF inflammatory signaling pathway, thereby effectively countering CCl4-induced chronic liver injury. This study illustrates that the enrichment of A. muciniphila in the gut microbiota, mediated by DCA, enhances the production of secondary bile acids, thereby mitigating chronic liver injury induced by CCl4. The underlying mechanism may involve the inhibition of hepatic IL-17 and TNF signaling pathways. These findings propose a promising approach to alleviate chronic liver injury by modulating both the gut microbiota and bile acids metabolism.

Dietary resistant starch supplementation increases gut luminal deoxycholic acid abundance in mice.

Bile acids (BA) are among the most abundant metabolites produced by the gut microbiome. Primary BAs produced in the liver are converted by gut bacterial 7-α-dehydroxylation into secondary BAs, which can differentially regulate host health via signaling based on their varying affinity for BA receptors. Despite the importance of secondary BAs in host health, the regulation of 7-α-dehydroxylation and the role of diet in modulating this process is incompletely defined. Understanding this process could lead to dietary guidelines that beneficially shift BA metabolism. Dietary fiber regulates gut microbial composition and metabolite production. We tested the hypothesis that feeding mice a diet rich in a fermentable dietary fiber, resistant starch (RS), would alter gut bacterial BA metabolism. Male and female wild-type mice were fed a diet supplemented with RS or an isocaloric control diet (IC). Metabolic parameters were similar between groups. RS supplementation increased gut luminal deoxycholic acid (DCA) abundance. However, gut luminal cholic acid (CA) abundance, the substrate for 7-α-dehydroxylation in DCA production, was unaltered by RS. Further, RS supplementation did not change the mRNA expression of hepatic BA producing enzymes or ileal BA transporters. Metagenomic assessment of gut bacterial composition revealed no change in the relative abundance of bacteria known to perform 7-α-dehydroxylation. P. ginsenosidimutans and P. multiformis were positively correlated with gut luminal DCA abundance and increased in response to RS supplementation. These data demonstrate that RS supplementation enriches gut luminal DCA abundance without increasing the relative abundance of bacteria known to perform 7-α-dehydroxylation.

Impact of De Novo Cholesterol Biosynthesis on the Initiation and Progression of Breast Cancer.

Cholesterol (CHOL) is a multifaceted lipid molecule. It is an essential structural component of cell membranes, where it cooperates in regulating the intracellular trafficking and signaling pathways. Additionally, it serves as a precursor for vital biomolecules, including steroid hormones, isoprenoids, vitamin D, and bile acids. Although CHOL is normally uptaken from the bloodstream, cells can synthesize it de novo in response to an increased requirement due to physiological tissue remodeling or abnormal proliferation, such as in cancer. Cumulating evidence indicated that increased CHOL biosynthesis is a common feature of breast cancer and is associated with the neoplastic transformation of normal mammary epithelial cells. After an overview of the multiple biological activities of CHOL and its derivatives, this review will address the impact of de novo CHOL production on the promotion of breast cancer with a focus on mammary stem cells. The review will also discuss the effect of de novo CHOL production on in situ and invasive carcinoma and its impact on the response to adjuvant treatment. Finally, the review will discuss the present and future therapeutic strategies to normalize CHOL biosynthesis.

Maternal exposure to 4-vinylcyclohexene diepoxide during pregnancy leads to disorder of gut microbiota and bile acid metabolism in offspring.

Our previous study reveals that maternal exposure to 4-vinylcyclohexene diepoxide (VCD) during pregnancy causes insufficient ovarian follicle reserve and decreased fertility in offspring. The present study aims to further explore the reasons for the significant decline of fecundity in mice caused by VCD, and to clarify the changes of gut microbiota and microbial metabolites in F1 mice. The ovarian metabolomics, gut microbiota and microbial metabolites were analyzed. The results of ovarian metabolomics analysis showed that maternal VCD exposure during pregnancy significantly reduced the concentration of carnitine in the ovaries of F1 mice, while supplementation with carnitine (isovalerylcarnitine and valerylcarnitine) significantly increased the number of ovulation. The results of 16 S rDNA-seq and microbial metabolites analysis showed that maternal VCD exposure during pregnancy caused disordered gut microbiota, increased abundance of Parabacteroides and Flexispira bacteria that are involved in secondary bile acid synthesis. The concentrations of NorDCA, LCA-3S, DCA and other secondary bile acids increased significantly. Our results indicate that maternal exposure to VCD during pregnancy leads to disorder in gut microbiota and bile acid metabolism in F1 mice, accompanying with decreased ovarian function, providing further evidence that maternal exposure to VCD during pregnancy has intergenerational deleterious effects on offspring.