Probiotic Lactobacillus rhamnosus GG Prevents Liver Fibrosis Through Inhibiting Hepatic Bile Acid Synthesis and Enhancing Bile Acid Excretion in Mice

Gut Microbiota and Liver Regeneration: A Synthesis of Evidence on Structural Changes and Physiological Mechanisms

Liver regeneration (LR) is a unique biological process with the ability to restore up to 70% of the organ. This allows for the preservation of liver resections for various liver tumors and for living donor liver transplantation (LDLT). However, in some cases, LR is insufficient and interventions that can improve LR are urgently needed. Gut microbiota (GM) is one of the factors influencing LR, as the liver and intestine are intimately connected through the gut-liver axis. Thus, healthy GM facilitates normal LR, whereas dysbiosis leads to impaired LR due to imbalance of bile acids, inflammatory cytokines, microbial metabolites, signaling pathways, etc. Therefore, GM can be considered as a new possible therapeutic target to improve LR. In this review, we critically observe the current knowledge about the influence of gut microbiota (GM) on liver regeneration (LR) and the possibility to improve this process, which may reduce complication and mortality rates after liver surgery. Although much research has been done on this topic, more clinical trials and systemic reviews are urgently needed to move this type of intervention from the experimental phase to the clinical field.

Lacticaseibacillus rhamnosus GG alleviates sleep deprivation-induced intestinal barrier dysfunction and neuroinflammation in mice

Consuming probiotic products is a solution that people are willing to choose to augment health. As a global health hazard, sleep deprivation (SD) can cause both physical and mental diseases. The present study investigated the protective effects of Lacticaseibacillus rhamnosus GG (LGG), a widely used probiotic, on a SD mouse model. Here, it has been shown that SD induced intestinal damage in mice, while LGG supplementation attenuated disruption of the intestinal barrier and enhanced the antioxidant capacity. Microbiome analysis revealed that SD caused dysbiosis in the gut microbiota, characterized by increased levels of Clostridium XlVa, Alistipes, and Desulfovibrio, as well as decreased levels of Ruminococcus, which were partially ameliorated by LGG. Moreover, SD resulted in elevated pro-inflammatory cytokine concentrations in both the intestine and the brain, while LGG provided protection in both organs. LGG supplementation significantly improved locomotor activity in SD mice. Although heat-killed LGG showed some protective effects in SD mice, its overall efficacy was inferior to that of live LGG. In terms of mechanism, it was found that AG1478, an inhibitor of the epidermal growth factor receptor (EGFR) tyrosine kinase, could diminish the protective effects of LGG. In conclusion, LGG demonstrated the ability to alleviate SD-induced intestinal barrier dysfunction through EGFR activation and alleviate neuroinflammation.

Biliary fibrosis is an important but neglected pathological feature in hepatobiliary disorders: from molecular mechanisms to clinical implications

Fibrosis resulting from pathological repair secondary to recurrent or persistent tissue damage often leads to organ failure and mortality. Biliary fibrosis is a crucial but easily neglected pathological feature in hepatobiliary disorders, which may promote the development and progression of benign and malignant biliary diseases through pathological healing mechanisms secondary to biliary tract injuries. Elucidating the etiology and pathogenesis of biliary fibrosis is beneficial to the prevention and treatment of biliary diseases. In this review, we emphasized the importance of biliary fibrosis in cholangiopathies and summarized the clinical manifestations, epidemiology, and aberrant cellular composition involving the biliary ductules, cholangiocytes, immune system, fibroblasts, and the microbiome. We also focused on pivotal signaling pathways and offered insights into ongoing clinical trials and proposing a strategic approach for managing biliary fibrosis-related cholangiopathies. This review will offer a comprehensive perspective on biliary fibrosis and provide an important reference for future mechanism research and innovative therapy to prevent or reverse fibrosis.

Total flavonoids of litchi Seed alleviates schistosomiasis liver fibrosis in mice by suppressing hepatic stellate cells activation and modulating the gut microbiomes

Infection with Schistosoma japonicum (S. japonicum) is an important zoonotic parasitic disease that causes liver fibrosis in both human and domestic animals. The activation of hepatic stellate cells (HSCs) is a crucial phase in the development of liver fibrosis, and inhibiting their activation can alleviate this progression. Total flavonoids of litchi seed (TFL) is a naturally extracted drug, and modern pharmacological studies have shown its anti-fibrotic and liver-protective effects. However, the role of TFL in schistosomiasis liver fibrosis is still unclear. This study investigated the therapeutic effects of TFL on liver fibrosis in S. japonicum infected mice and explored its potential mechanisms. Animal study results showed that TFL significantly reduced the levels of Interleukin-1β (IL-1β), Tumor Necrosis Factor-α (TNF-α), Interleukin-4 (IL-4), and Interleukin-6 (IL-6) in the serum of S. japonicum infected mice. TFL reduced the spleen index of mice and markedly improved the pathological changes in liver tissues induced by S. japonicum infection, decreasing the expression of alpha-smooth muscle actin (α-SMA), Collagen I and Collagen III protein in liver tissues. In vitro studies indicated that TFL also inhibited the activation of HCSs induced by Transforming Growth Factor-β1 (TGF-β1) and reduced the levels of α-SMA. Gut microbes metagenomics study revealed that the composition, abundance, and functions of the mice gut microbiomes changed significantly after S. japonicum infection, and TLF treatment reversed these changes. Therefore, our study indicated that TFL alleviated granulomatous lesions and improved S. japonicum induced liver fibrosis in mice by inhibiting the activation of HSCs and by improving the gut microbiomes.

Farnesoid X receptor: From Structure to Function and Its Pharmacology in Liver Fibrosis

The farnesoid X receptor (FXR), a ligand-activated transcription factor, plays a crucial role in regulating bile acid metabolism within the enterohepatic circulation. Beyond its involvement in metabolic disorders and immune imbalances affecting various tissues, FXR is implicated in microbiota modulation, gut-to-brain communication, and liver disease. The liver, as a pivotal metabolic and detoxification organ, is susceptible to damage from factors such as alcohol, viruses, drugs, and high-fat diets. Chronic or recurrent liver injury can culminate in liver fibrosis, which, if left untreated, may progress to cirrhosis and even liver cancer, posing significant health risks. However, therapeutic options for liver fibrosis remain limited in terms of FDA-approved drugs. Recent insights into the structure of FXR, coupled with animal and clinical investigations, have shed light on its potential pharmacological role in hepatic fibrosis. Progress has been achieved in both fundamental research and clinical applications. This review critically examines recent advancements in FXR research, highlighting challenges and potential mechanisms underlying its role in liver fibrosis treatment.

Lactobacillus rhamnosus GG ameliorates triptolide-induced liver injury through modulation of the bile acid-FXR axis

Triptolide (TP) is the principal bioactive compound of Tripterygium wilfordii with significant anti-tumor, anti-inflammatory and immunosuppressive activities. However, its severe hepatotoxicity greatly limits its clinical use. The underlying mechanism of TP-induced liver damage is still poorly understood. Here, we estimate the role of the gut microbiota in TP hepatotoxicity and investigate the bile acid metabolism mechanisms involved. The results of the antibiotic cocktail (ABX) and fecal microbiota transplantation (FMT) experiment demonstrate the involvement of intestinal flora in TP hepatotoxicity. Moreover, TP treatment significantly perturbed gut microbial composition and reduced the relative abundances of Lactobacillus rhamnosus GG (LGG). Supplementation with LGG reversed TP-induced hepatotoxicity by increasing bile salt hydrolase (BSH) activity and reducing the increased conjugated bile acids (BA). LGG supplementation upregulates hepatic FXR expression and inhibits NLRP3 inflammasome activation in TP-treated mice. In summary, this study found that gut microbiota is involved in TP hepatotoxicity. LGG supplementation protects mice against TP-induced liver damage. The underlying mechanism was associated with the gut microbiota-BA-FXR axis. Therefore, LGG holds the potential to prevent and treat TP hepatotoxicity in the clinic.

Role of gut/liver metabolites and gut microbiota in liver fibrosis caused by cholestasis

AIM OF THE STUDY

Cholestasis induces severe liver injury and subsequent liver fibrosis. However, a comprehensive understanding of the relationships between liver fibrosis and cholestasis-induced changes in metabolites in the gut and fibrotic liver tissue and in the gut microbiota is insufficient.

METHODS

Common bile duct ligation (BDL) was employed to establish a cholestatic liver fibrosis model in mice for 26 days. Fibrotic liver tissue and the gut contents were collected. Untargeted metabolomics was conducted for the determination of metabolites in the gut contents and liver tissues. Metagenomics was adopted to explore the gut microbiota.

RESULTS

The metabolites in the gut contents and liver tissues between normal and cholestatic liver fibrosis mice were highly distinct. Beta-alanine metabolism and glutathione metabolism were downregulated in the gut of the BDL group. Galactose metabolism, biosynthesis of unsaturated fatty acids, and ABC transporters were upregulated in the gut and downregulated in the liver of the BDL group. Arginine biosynthesis, taurine and hypotaurine metabolism, arginine and proline metabolism, and primary bile acid biosynthesis were downregulated in the gut and upregulated in the liver of the BDL group. Metagenomic analysis revealed that the alpha diversity of the microbiota in the BDL group decreased. The altered structure of the gut microbiota in the BDL group led to the hypofunction of important metabolic pathways (such as folate biosynthesis, histidine metabolism, thiamine metabolism, biotin metabolism, and phenylalanine, tyrosine and tryptophan biosynthesis) and enzymes (such as NADH, DNA helicase, and DNA-directed DNA polymerase). Correlation analyses indicated that certain gut microbes were associated with gut and liver metabolites.

CONCLUSIONS

Untargeted metabolomics and metagenomics provided comprehensive information on gut and liver metabolism and gut microbiota in mice with cholestatic liver fibrosis. Therefore, significantly altered bacteria and metabolites may help provide some targets against cholestatic liver fibrosis in the future.

Christensenella minuta Alleviates Acetaminophen-Induced Hepatotoxicity by Regulating Phenylalanine Metabolism

Acetaminophen (APAP)-induced liver injury (AILI), even liver failure, is a significant challenge due to the limited availability of therapeutic medicine. Christensenella minuta (C. minuta), as a probiotic therapy, has shown promising prospects in metabolism and inflammatory diseases. Our research aimed to examine the influence of C. minuta on AILI and explore the molecular pathways underlying it. We found that administration of C. minuta remarkably alleviated AILI in a mouse model, as evidenced by decreased levels of alanine transaminase (ALT) and aspartate aminotransferase (AST) and improvements in the histopathological features of liver sections. Additionally, there was a notable decrease in malondialdehyde (MDA), accompanied by restoration of the reduced glutathione/oxidized glutathione (GSH/GSSG) balance, and superoxide dismutase (SOD) activity. Furthermore, there was a significant reduction in inflammatory markers (IL6, IL1β, TNF-α). C. minuta regulated phenylalanine metabolism. No significant difference in intestinal permeability was observed in either the model group or the treatment group. High levels of phenylalanine aggravated liver damage, which may be linked to phenylalanine-induced dysbiosis and dysregulation in cytochrome P450 metabolism, sphingolipid metabolism, the PI3K-AKT pathway, and the Integrin pathway. Furthermore, C. minuta restored the diversity of the microbiota, modulated metabolic pathways and MAPK pathway. Overall, this research demonstrates that supplementing with C. minuta offers both preventive and remedial benefits against AILI by modulating the gut microbiota, phenylalanine metabolism, oxidative stress, and the MAPK pathway, with high phenylalanine supplementation being identified as a risk factor exacerbating liver injury.

Mitigation of high-fat diet-induced hepatic steatosis by thyme (Thymus quinquecostatus Celak) polyphenol-rich extract (TPE): insights into gut microbiota modulation and bile acid metabolism

Our previous study demonstrated that thyme polyphenol-rich extract (TPE) mitigated hepatic injury induced by a high-fat diet (HFD) through the regulation of lipid metabolism, promotion of short-chain fatty acid production, enhancement of intestinal barrier function, and attenuation of inflammation. In this study, we aimed to further elucidate additional mechanisms underlying TPE-mediated preventive effects on hepatic steatosis, with a specific focus on its impact on the gut microbiota and bile acid (BA) metabolism in HFD-fed mice. TPE treatment resulted in a significant reduction in serum total BA levels and a notable increase in fecal total BA levels. In particular, elevations in fecal conjugated BA levels, in turn, impede intestinal farnesoid X receptor (FXR) signaling, thereby enhancing hepatic synthesis and fecal excretion of BAs. The downregulated mRNA expression levels of intestinal Fxr and Fgf15, and hepatic Fgfr4, along with the upregulated mRNA expression levels of Cyp7a1 and Cyp27a1 after TPE treatment also prove the above inference. Meanwhile, TPE appeared to promote BA efflux and enterohepatic circulation, as evidenced by changes in the mRNA levels of Bsep, Ntpc, Shp, Asbt, Ibabp, and Ostα/β. TPE also modulated the gut microbiota and was characterized by an increased relative abundance of Lactobacillus. Furthermore, antibiotic treatment depleted the intestinal flora in mice, also abrogating the hepatoprotective effect of TPE against NAFLD. These findings collectively indicate that TPE effectively mitigates HFD-induced NAFLD by modulating the gut-liver axis, specifically targeting the gut microbiota and bile acid metabolism.

Metagenomic comparison of intestinal microbiota between normal and liver fibrotic rhesus macaques (Macaca mulatta)

Liver fibrosis is an important pathological process in chronic liver disease and cirrhosis. Recent studies have found a close association between intestinal microbiota and the development of liver fibrosis. To determine whether there are differences in the intestinal microbiota between rhesus macaques with liver fibrosis (MG) and normal rhesus macaques (MN), fecal samples were collected from 8 male MG and 12 male MN. The biological composition of the intestinal microbiota was then detected using 16S rRNA gene sequencing. The results revealed statistically significant differences in ASVs and Chao1 in the alpha-diversity and the beta-diversity of intestinal microbiota between MG and MN. Both groups shared Prevotella and Lactobacillus as common dominant microbiota. However, beneficial bacteria such as Lactobacillus were significantly less abundant in MG (P = 0.02). Predictive functional analysis using PICRUSt2 gene prediction revealed that MG exhibited a higher relative abundance of functions related to substance transport and metabolic pathways. This study may provide insight into further exploration of the mechanisms by which intestinal microbiota affect liver fibrosis and its potential future use in treating liver fibrosis.

FGF21-dependent alleviation of cholestasis-induced liver fibrosis by sodium butyrate

Background

The beneficial effects of fibroblast growth factor 21 (FGF21) and sodium butyrate (NaB) on protection against cholestasis-induced liver fibrosis are not well known. This study aimed to explore the effects of FGF21 and NaB on bile duct ligation (BDL)-induced liver fibrosis.

Methods

Wild-type (WT) and FGF21 knockout (KO) mice received BDL surgery for 14 days. Liver fibrosis was assessed by Masson's staining for fibrosis marker expressions at the mRNA or protein levels. Adenovirus-mediated FGF21 overexpression in the WT mice was assessed against BDL damage. BDL surgeries were performed in WT and FGF21 KO mice that were administered either phosphate-buffered saline or NaB. The effects of NaB on the energy metabolism and gut microbiota were assessed using stable metabolism detection and 16S rRNA gene sequencing.

Results

BDL-induced liver fibrosis in the WT mice was accompanied by high induction of FGF21. Compared to the WT mice, the FGF21 KO mice showed more severe liver fibrosis induced by BDL. FGF21 overexpression protected against BDL-induced liver fibrosis, as proved by the decreasing α-SMA at both the mRNA and protein levels. NaB administration enhanced the glucose and energy metabolisms as well as remodeled the gut microbiota. NaB alleviated BDL-induced liver fibrosis in the WT mice but aggravated the same in FGF21 KO mice.

Conclusion

FGF21 plays a key role in alleviating cholestasis-induced liver damage and fibrosis. NaB has beneficial effects on cholestasis in an FGF21-dependent manner. NaB administration can thus be a novel nutritional therapy for treating cholestasis via boosting FGF21 signaling and regulating the gut microbiota.

Picroside II promotes HSC apoptosis and inhibits the cholestatic liver fibrosis in Mdr2-/- mice by polarizing M1 macrophages and balancing immune responses

Liver fibrosis is characterized by chronic inflammatory responses and progressive fibrous scar formation. Macrophages play a central role in the pathogenesis of hepatic fibrosis by reconstructing the immune microenvironment. Picroside II (PIC II), extracted from Picrorhizae Rhizoma, has demonstrated therapeutic potential for various liver damage. However, the mechanisms by which macrophage polarization initiates immune cascades and contributes to the development of liver fibrosis, and whether this process can be influenced by PIC II, remain unclear. In the current study, RNA sequencing and multiple molecular approaches were utilized to explore the underlying mechanisms of PIC II against liver fibrosis in multidrug-resistance protein 2 knockout (Mdr2-/-) mice. Our findings indicate that PIC II activates M1-polarized macrophages to recruit natural killer cells (NK cells), potentially via the CXCL16-CXCR6 axis. Additionally, PIC II promotes the apoptosis of activated hepatic stellate cells (aHSCs) and enhances the cytotoxic effects of NK cells, while also reducing the formation of neutrophil extracellular traps (NETs). Notably, the anti-hepatic fibrosis effects associated with PIC II were largely reversed by macrophage depletion in Mdr2-/- mice. Collectively, our research suggests that PIC II is a potential candidate for halting the progression of liver fibrosis.

Therapeutic manipulation of the microbiome in liver disease

Myriad associations between the microbiome and various facets of liver physiology and pathology have been described in the literature. Building on descriptive and correlative sequencing studies, metagenomic studies are expanding our collective understanding of the functional and mechanistic role of the microbiome as mediators of the gut-liver axis. Based on these mechanisms, the functional activity of the microbiome represents an attractive, tractable, and precision medicine therapeutic target in several liver diseases. Indeed, several therapeutics have been used in liver disease even before their description as a microbiome-dependent approach. To bring successful microbiome-targeted and microbiome-inspired therapies to the clinic, a comprehensive appreciation of the different approaches to influence, collaborate with, or engineer the gut microbiome to coopt a disease-relevant function of interest in the right patient is key. Herein, we describe the various levels at which the microbiome can be targeted-from prebiotics, probiotics, synbiotics, and antibiotics to microbiome reconstitution and precision microbiome engineering. Assimilating data from preclinical animal models, human studies as well as clinical trials, we describe the potential for and rationale behind studying such therapies across several liver diseases, including metabolic dysfunction-associated steatotic liver disease, alcohol-associated liver disease, cirrhosis, HE as well as liver cancer. Lastly, we discuss lessons learned from previous attempts at developing such therapies, the regulatory framework that needs to be navigated, and the challenges that remain.

Peripherally Restricted CB1 Receptor Inverse Agonist JD5037 Treatment Exacerbates Liver Injury in MDR2-Deficient Mice

Previous research highlighted the involvement of the cannabinoid CB1 receptor in regulating the physiology of hepatocytes and hepatic stellate cells. The inhibition of the CB1 receptor via peripherally restricted CB1 receptor inverse agonist JD5037 has shown promise in inhibiting liver fibrosis in mice treated with CCl4. However, its efficacy in phospholipid transporter-deficiency-induced liver fibrosis remains uncertain. In this study, we investigated the effectiveness of JD5037 in Mdr2-/- mice. Mdr2 (Abcb4) is a mouse ortholog of the human MDR3 (ABCB4) gene encoding for the canalicular phospholipid transporter. Genetic disruption of the Mdr2 gene in mice causes a complete absence of phosphatidylcholine from bile, leading to liver injury and fibrosis. Mdr2-/- mice develop spontaneous fibrosis during growth. JD5037 was orally administered to the mice for four weeks starting at eight weeks of age. Liver fibrosis, bile acid levels, inflammation, and injury were assessed. Additionally, JD5037 was administered to three-week-old mice to evaluate its preventive effects on fibrosis development. Our findings corroborate previous observations regarding global CB1 receptor inverse agonists. Four weeks of JD5037 treatment in eight-week-old Mdr2-/- mice with established fibrosis led to reduced body weight gains. However, contrary to expectations, JD5037 significantly exacerbated liver injury, evidenced by elevated serum ALT and ALP levels and exacerbated liver histology. Notably, JD5037-treated Mdr2-/- mice exhibited significantly heightened serum bile acid levels. Furthermore, JD5037 treatment intensified liver fibrosis, increased fibrogenic gene expression, stimulated ductular reaction, and upregulated hepatic proinflammatory cytokines. Importantly, JD5037 failed to prevent liver fibrosis formation in three-week-old Mdr2-/- mice. In summary, our study reveals the exacerbating effect of JD5037 on liver fibrosis in genetically MDR2-deficient mice. These findings underscore the need for caution in the use of peripherally restricted CB1R inverse agonists for liver fibrosis treatment, particularly in cases of dysfunctional hepatic phospholipid transporter.

Regulating bile acids signaling for NAFLD: molecular insights and novel therapeutic interventions

Nonalcoholic fatty liver disease (NAFLD) emerges as the most predominant cause of liver disease, tightly linked to metabolic dysfunction. Bile acids (BAs), initially synthesized from cholesterol in the liver, undergo further metabolism by gut bacteria. Increasingly acknowledged as critical modulators of metabolic processes, BAs have been implicated as important signaling molecules. In this review, we will focus on the mechanism of BAs signaling involved in glucose homeostasis, lipid metabolism, energy expenditure, and immune regulation and summarize their roles in the pathogenesis of NAFLD. Furthermore, gut microbiota dysbiosis plays a key role in the development of NAFLD, and the interactions between BAs and intestinal microbiota is elucidated. In addition, we also discuss potential therapeutic strategies for NAFLD, including drugs targeting BA receptors, modulation of intestinal microbiota, and metabolic surgery.

Association between blood lipid levels and the risk of liver cancer: a systematic review and meta-analysis

PURPOSE

The association between blood lipid levels and the risk of developing liver cancer remains a subject of ongoing debate. To elucidate this association, we conducted a meta-analysis by systematically incorporating data from all relevant prospective cohort studies.

METHODS

We conducted a systematic search of the PubMed, Embase, Web of Science, and Cochrane Library databases covering studies published from database inception through July 2023. This study included prospective cohort studies related to lipid profiles (e.g., total cholesterol (TC), triglyceride (TG), high-density lipoprotein cholesterol (HDL-C), and low-density lipoprotein cholesterol (LDL-C) levels) that reported hazard ratios (HRs) or relative risks (RRs) with corresponding 95% confidence intervals (95% CIs) to investigate their association with the risk of liver cancer. During the analysis process, we used fixed-effects or random-effects models based on the level of heterogeneity among the studies and obtained pooled risk ratios using these models. To ensure the robustness and reliability of the study findings, we also conducted sensitivity analyses and publication bias analyses.

RESULTS

After conducting a systematic search, 12 studies were identified from a total of 11,904 articles and were included in the meta-analysis. These studies included a combined population of 10,765,221 participants, among whom 31,055 cases of liver cancer were reported. The analysis revealed that the pooled HR for the serum TC concentration (highest versus lowest) was 0.45 (95% CI = 0.35-0.58, I2 = 78%). For TGs, the HR was 0.67 (95% CI = 0.46-0.96, I2 = 86%), while for HDL-C, the HR was 0.72 (95% CI = 0.58-0.90, I2 = 65%). The HR for LDL-C was 0.51 (95% CI = 0.23-1.13, I2 = 93%).

CONCLUSION

The findings of this study indicate that serum TC, TG, and HDL-C levels are negatively associated with liver cancer risk, suggesting that higher concentrations of these lipids are associated with a reduced risk of liver cancer. However, no significant association has been found between LDL-C levels and liver cancer risk.

The role of the microbiome in liver disease

PURPOSE OF REVIEW

The intestinal microbiome and the gut-liver axis play a major role in health and disease. The human gut harbors trillions of microbes and a disruption of the gut homeostasis can contribute to liver disease. In this review, the progress in the field within the last 3 years is summarized, focusing on metabolic dysfunction-associated steatotic liver disease (MASLD), alcohol-associated liver disease (ALD), autoimmune liver disease (AILD), and hepatocellular carcinoma (HCC).

RECENT FINDINGS

Changes in the fecal virome and fungal mycobiome have been described in patients with various liver diseases. Several microbial derived metabolites including endogenous ethanol produced by bacteria, have been mechanistically linked to liver disease such as MASLD. Virulence factors encoded by gut bacteria contribute to ALD, AILD and HCC. Novel therapeutic approaches focused on the microbiome including phages, pre- and postbiotics have been successfully used in preclinical models. Fecal microbiota transplantation has been effective in attenuating liver disease. Probiotics are safe in patients with alcohol-associated hepatitis and improve liver disease and alcohol addiction.

SUMMARY

The gut-liver axis plays a key role in the pathophysiology of liver diseases. Understanding the microbiota in liver disease can help to develop precise microbiota centered therapies.

Molecular insights into experimental models and therapeutics for cholestasis

Cholestatic liver disease (CLD) is a range of conditions caused by the accumulation of bile acids (BAs) or disruptions in bile flow, which can harm the liver and bile ducts. To investigate its pathogenesis and treatment, it is essential to establish and assess experimental models of cholestasis, which have significant clinical value. However, owing to the complex pathogenesis of cholestasis, a single modelling method can merely reflect one or a few pathological mechanisms, and each method has its adaptability and limitations. We summarize the existing experimental models of cholestasis, including animal models, gene-knockout models, cell models, and organoid models. We also describe the main types of cholestatic disease simulated clinically. This review provides an overview of targeted therapy used for treating cholestasis based on the current research status of cholestasis models. In addition, we discuss the respective advantages and disadvantages of different models of cholestasis to help establish experimental models that resemble clinical disease conditions. In sum, this review not only outlines the current research with cholestasis models but also projects prospects for clinical treatment, thereby bridging basic research and practical therapeutic applications.

Exploring Advanced Therapies for Primary Biliary Cholangitis: Insights from the Gut Microbiota-Bile Acid-Immunity Network

Primary biliary cholangitis (PBC) is a cholestatic liver disease characterized by immune-mediated injury to small bile ducts. Although PBC is an autoimmune disease, the effectiveness of conventional immunosuppressive therapy is disappointing. Nearly 40% of PBC patients do not respond to the first-line drug UDCA. Without appropriate intervention, PBC patients eventually progress to liver cirrhosis and even death. There is an urgent need to develop new therapies. The gut-liver axis emphasizes the interconnection between the gut and the liver, and evidence is increasing that gut microbiota and bile acids play an important role in the pathogenesis of cholestatic diseases. Dysbiosis of gut microbiota, imbalance of bile acids, and immune-mediated bile duct injury constitute the triad of pathophysiology in PBC. Autoimmune cholangitis has the potential to be improved through immune system modulation. Considering the failure of conventional immunotherapies and the involvement of gut microbiota and bile acids in the pathogenesis, targeting immune factors associated with them, such as bile acid receptors, microbial-derived molecules, and related specific immune cells, may offer breakthroughs. Understanding the gut microbiota-bile acid network and related immune dysfunctions in PBC provides a new perspective on therapeutic strategies. Therefore, we summarize the latest advances in research of gut microbiota and bile acids in PBC and, for the first time, explore the possibility of related immune factors as novel immunotherapy targets. This article discusses potential therapeutic approaches focusing on regulating gut microbiota, maintaining bile acid homeostasis, their interactions, and related immune factors.

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.

Suppression of P2X4 and P2X7 by Lactobacillus rhamnosus vitaP1: effects on hangover symptoms

This study aimed to identify substances including Lactobacillus rhamnosus vitaP1 (KACC 92054P) that alleviate hangover-induced emotional anxiety and liver damage. The association between emotional anxiety caused by hangover and the genes P2X4, P2X7, SLC6A4 was investigated. In vitro and in vivo analyses were conducted to assess the influence of free-panica on alcohol-induced upregulated gene expression. Additionally, the concentration of AST, ALT, alcohol, and acetaldehyde in blood was measured. Free-panica, consisting of five natural products (Phyllanthus amarus, Phoenix dactylifera, Vitis vinifera, Zingiber officinale, and Lactobacillus rhamnosus), were evaluated for their regulatory effects on genes involved in alcohol-induced emotional anxiety and liver damage. The combination of these natural products in free-panica successfully restored emotional anxiety, and the concentration of AST, ALT, alcohol, and acetaldehyde in blood to those of the normal control group. These findings support the potential development of free-panica as a health functional food or medicinal intervention for relieving hangover symptoms and protecting liver from alcohol consumption.

Natural Products in the Modulation of Farnesoid X Receptor Against Nonalcoholic Fatty Liver Disease

Nonalcoholic fatty liver disease (NAFLD) is a global health concern with a high prevalence and increasing economic burden, but official medicine remains unavailable. Farnesoid X receptor (FXR), a nuclear receptor member, is one of the most promising drug targets for NAFLD therapy that plays a crucial role in modulating bile acid, glucose, and lipid homeostasis, as well as inhibits hepatic inflammation and fibrosis. However, the rejection of the FXR agonist, obecholic acid, by the Food and Drug Administration for treating hepatic fibrosis raises a question about the functions of FXR in NAFLD progression and the therapeutic strategy to be used. Natural products, such as FXR modulators, have become the focus of attention for NAFLD therapy with fewer adverse reactions. The anti-NAFLD mechanisms seem to act as FXR agonists and antagonists or are involved in the FXR signaling pathway activation, indicating a promising target of FXR therapeutic prospects using natural products. This review discusses the effective mechanisms of FXR in NAFLD alleviation, and summarizes currently available natural products such as silymarin, glycyrrhizin, cycloastragenol, berberine, and gypenosides, for targeting FXR, which can facilitate development of naturally targeted drug by medicinal specialists for effective treatment of NAFLD.

Research reviews and prospects of gut microbiota in liver cirrhosis: a bibliometric analysis (2001-2023)

INTRODUCTION

The gut-liver axis has emerged as a focal point in chronic liver disorders, prompting more research into the role of the gut microbiota in liver cirrhosis. In individuals with liver cirrhosis, changes in the structure and function of the gut microbiota are closely tied to clinical prognosis. However, there is a scarcity of bibliometric evaluations conducted in this particular field.

METHODS

This study is aiming to conduct a complete analysis of the knowledge structure and centers pertaining to gut microbiota in liver cirrhosis using bibliometric methods. Publications on gut microbiota and liver cirrhosis from 2001 to 2023 are sourced from the Web of Science Core Collection. For the bibliometric analysis, we employ VOSviewer, CiteSpace, and the R package "bibliometrix".

RESULTS

Our study encompasses a comprehensive collection of 3109 articles originating from 96 countries, with notable contributions from leading nations such as the United States and China. The quantity of publications concerning the gut microbiota of liver cirrhosis rises annually. The University of California San Diego, Virginia Commonwealth University, Zhejiang University are the primary research institutions. World Journal of Gastroenterology publishes the most papers in this field, while hepatology is the most frequently co-cited journal. These publications come from a total of 15,965 authors, and the most prolific authors are Bajaj Jasmohan S., Schnabl Bernd and Gillevet Patrick M., while the most co-cited authors are Bajaj Jasmohan S., Younossi Zobair M., and Reiner Wiest. In addition, "dysbiosis", "gut microbiota", "intestinal barrier", "fecal microbiota transplantation", and "complement-system" are the primary keywords of research trends in recent years.

DISCUSSION

This study offering a comprehensive insight into the research dynamics surrounding gut microbiota in patients with liver cirrhosis. It delineates the current research frontiers and hotspots, serving as a valuable guide for scholars.

Empagliflozin attenuates liver fibrosis in high-fat diet/streptozotocin-induced mice by modulating gut microbiota

The effects of SGLT2 inhibitors on hepatic fibrosis in diabetes remain unclear. This study aimed to investigate the effects of empagliflozin on liver fibrosis in high-fat diet/streptozotocin-induced mice and the correlation with gut microbiota. After the application of empagliflozin for 6 weeks, we performed oral glucose tolerance and intraperitoneal insulin tolerance tests to assess glucose tolerance and insulin resistance, and stained liver sections to evaluate histochemical and hepatic pathological markers of liver fibrosis. Moreover, 16S rRNA amplicon sequencing was performed on stool samples to explore changes in the composition of intestinal bacteria. We finally analysed the correlation between gut microbiome and liver fibrosis scores or indicators of glucose metabolism. The results showed that empagliflozin intervention improved glucose metabolism and liver function with reduced liver fibrosis, which might be related to changes in intestinal microbiota. In addition, the abundance of intestinal probiotic Lactobacillus increased, while Ruminococcus and Adlercreutzia decreased after empagliflozin treatment, and correlation analysis showed that the changes in microbiota were positively correlated with liver fibrosis and glucose metabolism. Overall, considering the contribution of the gut microbiota in metabolism, empagliflozin might have improved the beneficial balance of intestinal bacteria composition. The present study provides evidence and indicates the involvement of the gut-liver axis by SGLT2 inhibitors in T2DM with liver fibrosis.

Involvement of Bile Acid Metabolism and Gut Microbiota in the Amelioration of Experimental Metabolism-Associated Fatty Liver Disease by Nobiletin

Metabolism-associated fatty liver disease (MAFLD), a growing health problem worldwide, is one of the major risks for the development of cirrhosis and liver cancer. Oral administration of nobiletin (NOB), a natural citrus flavonoid, modulates the gut microbes and their metabolites in mice. In the present study, we established a mouse model of MAFLD by subjecting mice to a high-fat diet (HFD) for 12 weeks. Throughout this timeframe, NOB was administered to investigate its potential benefits on gut microbial balance and bile acid (BA) metabolism using various techniques, including 16S rRNA sequencing, targeted metabolomics of BA, and biological assays. NOB effectively slowed the progression of MAFLD by reducing serum lipid levels, blood glucose levels, LPS levels, and hepatic IL-1β and TNF-α levels. Furthermore, NOB reinstated diversity within the gut microbial community, increasing the population of bacteria that produce bile salt hydrolase (BSH) to enhance BA excretion. By exploring further, we found NOB downregulated hepatic expression of the farnesoid X receptor (FXR) and its associated small heterodimer partner (SHP), and it increased the expression of downstream enzymes, including cholesterol 7α-hydroxylase (CYP7A1) and cytochrome P450 27A1 (CYP27A1). This acceleration in cholesterol conversion within the liver contributes to mitigating MAFLD. The present findings underscore the significant role of NOB in regulating gut microbial balance and BA metabolism, revealing that long-term intake of NOB plays beneficial roles in the prevention or intervention of MAFLD.

Intestinal microbiota regulates the gut-thyroid axis: the new dawn of improving Hashimoto thyroiditis

Intestinal microbiota plays an indispensable role in the host's innate immune system, which may be related to the occurrence of many autoimmune diseases. Hashimoto thyroiditis (HT) is one of the most common autoimmune diseases, and there is plenty of evidence indicating that HT may be related to genetics and environmental triggers, but the specific mechanism has not been proven clearly. Significantly, the composition and abundance of intestinal microbiota in patients with HT have an obvious difference. This phenomenon led us to think about whether intestinal microbiota can affect the progress of HT through some mechanisms. By summarizing the potential mechanism of intestinal microflora in regulating Hashimoto thyroiditis, this article explores the possibility of improving HT by regulating intestinal microbiota and summarizes relevant biomarkers as therapeutic targets, which provide new ideas for the clinical diagnosis and treatment of Hashimoto thyroiditis.

Multispecies probiotics complex improves bile acids and gut microbiota metabolism status in an in vitro fermentation model

The consumption of probiotics has been extensively employed for the management or prevention of gastrointestinal disorders by modifying the gut microbiota and changing metabolites. Nevertheless, the probiotic-mediated regulation of host metabolism through the metabolism of bile acids (BAs) remains inadequately comprehended. The gut-liver axis has received more attention in recent years due to its association with BA metabolism. The objective of this research was to examine the changes in BAs and gut microbiota using an in vitro fermentation model. The metabolism and regulation of gut microbiota by commercial probiotics complex containing various species such as Lactobacillus, Bifidobacterium, and Streptococcus were investigated. The findings indicated that the probiotic strains had produced diverse metabolic profiles of BAs. The probiotics mixture demonstrated the greatest capacity for Bile salt hydrolase (BSH) deconjugation and 7α-dehydroxylation, leading to a significant elevation in the concentrations of Chenodeoxycholic acid, Deoxycholic acidcholic acid, and hyocholic acid in humans. In addition, the probiotic mixtures have the potential to regulate the microbiome of the human intestines, resulting in a reduction of isobutyric acid, isovaleric acid, hydrogen sulfide, and ammonia. The probiotics complex intervention group showed a significant increase in the quantities of Lactobacillus and Bifidobacterium strains, in comparison to the control group. Hence, the use of probiotics complex to alter gut bacteria and enhance the conversion of BAs could be a promising approach to mitigate metabolic disorders in individuals.

Bifidobacterium animalis subsp. lactis F1-7 Alleviates Lipid Accumulation in Atherosclerotic Mice via Modulating Bile Acid Metabolites to Downregulate Intestinal FXR

The dysfunction of intestinal microbiota and bile acid metabolism is related to the pathogenesis of atherosclerosis. This study we explored the mechanism of Bifidobacterium animalis subsp. lactis F1-7 (Bif. animalis F1-7), improving atherosclerosis by regulating the bile acid metabolism and intestinal microbiota in the ApoE-/- mice. The Bif. animalis F1-7 effectively reduced aortic plaque accumulation and improved the serum and liver lipid levels in atherosclerotic mice. The untargeted metabolomics revealed that Bif. animalis F1-7 reduced the glycine-conjugated bile acids and the levels of differential metabolite lithocholic acid (LCA) significantly. Downregulation of LCA decreased the intestinal levels of the farnesoid X-activated receptor (FXR) and regulated the bile acid metabolism through the FXR/FGF15/CYP7A1 pathway. Furthermore, the 16srRNA gene sequencing analysis revealed that structural changes in intestinal microbiota with an increase in the abundance of Bifidobacterium, Lactobacillus, Faecalibaculum, Desulfovibrio, and a decrease in Dubosiella, Clostridium_sensu_stricto_1, and Turicibacter following the Bif. animalis F1-7 intervention. Correlation analysis showed that the changes in intestinal microbiota mentioned above were significantly correlated with bile acid metabolism in atherosclerotic mice. In conclusion, this study sheds light on the mechanisms by which Bif. animalis F1-7 regulates atherosclerosis.

The Effect of Heat-Killed Lactobacillus plantarum on Oxidative Stress and Liver Damage in Rats with Bile Duct Ligation-Induced Hepatic Fibrosis

This study is aimed at evaluating the effects of heat-killed Lactobacillus plantarum (L. plantarum) on cholestatic liver injury induced by bile duct ligation (BDL) in rats. Rats in the first group were healthy (normal control) and in the second group underwent abdominal incision (sham control). Rats in the third and fourth groups underwent common bile duct ligation and were treated with either oral distilled water (BDL control group) or heat-killed L. plantarum (BDL + L. plantarum) for 28 days. Finally, rats were sacrificed, blood samples were analyzed through biochemical methods, liver and ileum tissue tissues were histologically assessed, and the expression of the αSMA, TNF-α, IL-6, and IL-10 genes in the liver and ZO-1 gene in ileum tissues were assessed through real-time PCR. The levels of bilirubin, liver function enzymes, NO, MDA, and carbonyl protein in the BDL + L. plantarum group were significantly lower than in the BDL control group (P ≤ 0.05). SOD and CAT activity in BDL + L. plantarum group was significantly greater than the BDL control group 1.4 and 3.0 times, respectively (P ≤ 0.001). Moreover, in the BDL + L. plantarum group, the expression of the α-SMA, TNF-α, and IL-6 genes was significantly lower (3.1, 2.9, and 2.5 times), and IL-10 and ZO-1 genes were significantly greater than the BDL control group by 2.1 and 3.6 times, respectively (P ≤ 0.05). The histological assessment also confirmed the greater effectiveness of heat-killed L. plantarum in improving the morphology and parenchymal structure of the liver. Taken together, our results suggest that heat-killed L. plantarum strains are potential therapeutic agents for hepatic fibrosis.

Therapeutic potential of berberine in attenuating cholestatic liver injury: insights from a PSC mouse model

BACKGROUND AND AIMS

Primary sclerosing cholangitis (PSC) is a chronic liver disease characterized by progressive biliary inflammation and bile duct injury. Berberine (BBR) is a bioactive isoquinoline alkaloid found in various herbs and has multiple beneficial effects on metabolic and inflammatory diseases, including liver diseases. This study aimed to examine the therapeutic effect of BBR on cholestatic liver injury in a PSC mouse model (Mdr2-/- mice) and elucidate the underlying mechanisms.

METHODS

Mdr2-/-mice (12-14 weeks old, both sexes) received either BBR (50 mg/kg) or control solution daily for eight weeks via oral gavage. Histological and serum biochemical analyses were used to assess fibrotic liver injury severity. Total RNAseq and pathway analyses were used to identify the potential signaling pathways modulated by BBR in the liver. The expression levels of key genes involved in regulating hepatic fibrosis, bile duct proliferation, inflammation, and bile acid metabolism were validated by qRT-PCR or Western blot analysis. The bile acid composition and levels in the serum, liver, small intestine, and feces and tissue distribution of BBR were measured by LC-MS/MS. Intestinal inflammation and injury were assessed by gene expression profiling and histological analysis. The impact on the gut microbiome was assessed using 16S rRNA gene sequencing.

RESULTS

BBR treatment significantly ameliorated cholestatic liver injury, evidenced by decreased serum levels of AST, ALT, and ALP, and reduced bile duct proliferation and hepatic fibrosis, as shown by H&E, Picro-Sirius Red, and CK19 IHC staining. RNAseq and qRT-PCR analyses indicated a substantial inhibition of fibrotic and inflammatory gene expression. BBR also mitigated ER stress by downregulating Chop, Atf4 and Xbp-1 expression. In addition, BBR modulated bile acid metabolism by altering key gene expressions in the liver and small intestine, resulting in restored bile acid homeostasis characterized by reduced total bile acids in serum, liver, and small intestine and increased fecal excretion. Furthermore, BBR significantly improved intestinal barrier function and reduced bacterial translocation by modulating the gut microbiota.

CONCLUSION

BBR effectively attenuates cholestatic liver injury, suggesting its potential as a therapeutic agent for PSC and other cholestatic liver diseases.

The supplementation of the multi-strain probiotics WHHPRO™ alleviates high-fat diet-induced metabolic symptoms in rats via gut-liver axis

Metabolic syndrome (MS) has emerged as one of the major global health concerns, accompanied by a series of related complications, such as obesity and type-2 diabetes. The gut-liver axis (GLA) is a bidirectional communication between the gut and the liver. The GLA alterations have been revealed to be closely associated with the development of MS. Probiotics within Lactobacillus and Bifidobacterium confer beneficial effects on improving MS symptoms. WHHPRO™ is a mixture of four probiotic strains, with potential MS-improving abilities. This study aimed to investigate the effects of WHHPRO™ on MS symptoms using a high-fat diet (HFD) rat model. Oral administration of WHHPRO™ for 12 weeks improved glucose tolerance, blood lipid, body weight, and liver index in HFD rats. WHHPRO™ shaped the gut microbiome composition by increasing the abundance of Lactobacillus and Akkermansia and normalized the reduced SCFA levels in HFD rats. Besides, WHHPRO™ modulated the fecal bile acids (BAs) profile, with decreased levels of T-b-MCA and 12-KDCA and increased levels of LCA and ILCA. Meanwhile, WHHPRO™ increased total unconjugated BAs in feces and liver and reduced the accumulation of total hepatic BA pool size in HFD rats. Moreover, WHHPRO™ reversed the expression of genes associated with impaired BA metabolism signaling in the ileum and liver. Our findings suggest that WHHPRO™ exerted beneficial effects on improving MS symptoms, involving the modulation of the gut microbiome composition, SCFAs, and the FXR-FGF15 signaling along the GLA. Supplementation of WHHPRO™ may serve as a novel strategy for improving MS symptoms.

Astragalus saponins protect against extrahepatic and intrahepatic cholestatic liver fibrosis models by activation of farnesoid X receptor

ETHNOPHARMACOLOGICAL RELEVANCE

Cholestatic Liver Fibrosis (CLF) is a hepatobiliary disease that typically arises as a late-stage complication of cholestasis, which can have multiple underlying causes. There are no satisfactory chemical or biological drugs for CLF. Total Astragalus saponins (TAS) are considered to be the main active constituents of the traditional Chinese herb Astragali Radix (AR), which has the obvious improvement effects for treating CLF. However, the mechanism of anti-CLF effects of TAS is still unclear.

AIM OF THE STUDY

The present study was undertaken to investigate the therapeutic effects of TAS against bile duct ligation (BDL) and 3, 5-diethoxycarbonyl-1,4-dihydroxychollidine (DDC) -induced CLF models and to reveal the potential mechanism to support its clinic use with scientific evidence.

MATERIALS AND METHODS

In this study, BDL-induced CLF rats were treated with TAS (20 mg/kg, 40 mg/kg) and DDC-induced CLF mice were treated with 56 mg/kg TAS. The therapeutic effects of TAS on extrahepatic and intrahepatic CLF models were evaluated by serum biochemical analysis, liver histopathology and hydroxyproline (Hyp). Thirty-nine individual bile acids (BAs) in serum and liver were quantified by using UHPLC-Q-Exactive Orbitrap HRMS. qRT-PCR, Western blot and immunohistochemistry analysis were used to measure the expression of liver fibrosis and ductular reaction markers, inflammatory factors and BAs related metabolic transporters, along with nuclear receptor farnesoid X receptor (FXR).

RESULTS

The serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total bilirubin (TBiL), direct bilirubin (DBiL) and contents of liver Hyp were dose-dependently improved after treatment for TAS in BDL and DDC- induced CLF models. And the increased levels of ALT and AST were significantly improved by total extract from Astragali radix (ASE) in BDL model. The liver fibrosis and ductular reaction markers, α-smooth muscle actin (α-SMA) and cytokeratin 19 (CK19), were significantly ameliorated in TAS group. And the liver expression of inflammatory factors: interleukin 6 (IL-6), tumor necrosis factor-α (TNF-α) and interleukin 1β (IL-1β) were significantly decreased after TAS treatment. In addition, TAS significantly ameliorated taurine-conjugated BAs (tau-BAs) levels, particularly α-TMCA, β-TMCA and TCA contents in serum and liver, which correlated with induced expressions of hepatic FXR and BAs secretion transporters. Furthermore, TAS significantly improved short heterodimer partner (SHP), cholesterol 7α-hydroxylase (Cyp7a1), Na+ taurocholate cotransport peptide (NTCP) and bile-salt export pump (BSEP) mRNA and protein expression.

CONCLUSIONS

TAS exerted a hepatoprotective effect against CLF by ameliorating liver injury, inflammation and restoring the altered tau-BAs metabolism to produce a positive regulatory effect on FXR-related receptors and transporters.

Interaction between Per- and Polyfluorinated Substances (PFAS) and Acetaminophen in Disease Exacerbation-Focusing on Autism and the Gut-Liver-Brain Axis

This review presents a new perspective on the exacerbation of autism spectrum disorder (ASD) by per- and polyfluoroalkyl substances (PFAS) through the gut-liver-brain axis. We have summarized evidence reported on the involvement of the gut microbiome and liver inflammation that led to the onset and exacerbation of ASD symptoms. As PFAS are toxicants that particularly target liver, this review has comprehensively explored the possible interaction between PFAS and acetaminophen, another liver toxicant, as the chemicals of interest for future toxicology research. Our hypothesis is that, at acute dosages, acetaminophen has the ability to aggravate the impaired conditions of the PFAS-exposed liver, which would further exacerbate neurological symptoms such as lack of social communication and interest, and repetitive behaviors using mechanisms related to the gut-liver-brain axis. This review discusses their potential interactions in terms of the gut-liver-brain axis and signaling pathways that may contribute to neurological diseases.

Melatonin improves cholestatic liver disease via the gut-liver axis

Cholestatic liver disease is characterized by disturbances in the intestinal microbiota and excessive accumulation of toxic bile acids (BA) in the liver. Melatonin (MT) can improve liver diseases. However, the underlying mechanism remains unclear. This study aimed to explore the mechanism of MT on hepatic BA synthesis, liver injury, and fibrosis in 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-fed and Mdr2-/- mice. MT significantly improved hepatic injury and fibrosis with a significant decrease in hepatic BA accumulation in DDC-fed and Mdr2-/- mice. MT reprogramed gut microbiota and augmented fecal bile salt hydrolase activity, which was related to increasing intestinal BA deconjugation and fecal BA excretion in both DDC-fed and Mdr2-/- mice. MT significantly activated the intestinal farnesoid X receptor (FXR)/fibroblast growth factor 15 (FGF-15) axis and subsequently inhibited hepatic BA synthesis in DDC-fed and Mdr2-/- mice. MT failed to improve DDC-induced liver fibrosis and BA synthesis in antibiotic-treated mice. Furthermore, MT provided protection against DDC-induced liver injury and fibrosis in fecal microbiota transplantation mice. MT did not decrease liver injury and fibrosis in DDC-fed intestinal epithelial cell-specific FXR knockout mice, suggesting that the intestinal FXR mediated the anti-fibrosis effect of MT. In conclusion, MT ameliorates cholestatic liver diseases by remodeling gut microbiota and activating intestinal FXR/FGF-15 axis-mediated inhibition of hepatic BA synthesis and promotion of BA excretion in mice.

Advancing lifelong precision medicine for cardiovascular diseases through gut microbiota modulation

The gut microbiome is known as the tenth system of the human body that plays a vital role in the intersection between health and disease. The considerable inter-individual variability in gut microbiota poses both challenges and great prospects in promoting precision medicine in cardiovascular diseases (CVDs). In this review, based on the development, evolution, and influencing factors of gut microbiota in a full life circle, we summarized the recent advances on the characteristic alteration in gut microbiota in CVDs throughout different life stages, and depicted their pathological links in mechanism, as well as the highlight achievements of targeting gut microbiota in CVDs prevention, diagnosis and treatment. Personalized strategies could be tailored according to gut microbiota characteristics in different life stages, including gut microbiota-blood metabolites combined prediction and diagnosis, dietary interventions, lifestyle improvements, probiotic or prebiotic supplements. However, to fulfill the promise of a lifelong cardiovascular health, more mechanism studies should progress from correlation to causality and decipher novel mechanisms linking specific microbes and CVDs. It is also promising to use the burgeoning artificial intelligence and machine learning to target gut microbiota for developing diagnosis system and screening for new therapeutic interventions.

Roles of Human Gut Microbiota in Liver Cirrhosis Risk: A Two-Sample Mendelian Randomization Study

BACKGROUND

Accumulating evidence suggests that alterations in gut microbiota composition and diversity are associated with liver cirrhosis. But whether gut microbiota promotes or hampers the genesis and development of liver cirrhosis remains vague.

OBJECTIVES

This study aimed to establish a causal relationship between gut microbiota and the development of liver fibrosis and cirrhosis. To achieve this, we employed a 2-sample Mendelian randomization (MR) analysis utilizing genome-wide association study (GWAS) summary statistics. This approach enabled us to assess the potential impact of gut microbiota on liver cirrhosis.

METHODS

The independent genetic instruments of gut microbiota were obtained from the MiBioGen (up to 18,340 participants), which is a large-scale genome-wide genotype and 16S fecal microbiome dataset. Cirrhosis data were derived from the FinnGen biobank analysis, which included 214,403 individuals of European ancestry (811 patients and 213,592 controls). To assess the causal relationship between gut microbiota and cirrhosis, we applied 4 different methods of MR analysis: the inverse-variance weighted method (IVW), the MR-Egger regression, the weighted median analysis (WME), and the weighted mode. Furthermore, sensitivity analyses were conducted to evaluate heterogeneity and horizontal pleiotropy.

RESULTS

Results of MR analyses provided evidence of a causal association between 4 microbiota features and cirrhosis, including 2 family [Lachnosiraceae: odds ratio (OR): 1.82626178; 95% confidence interval (CI): 1.05208209, 3.17012532; P = 0.0323194; Lactobacillaceae : OR: 0.62897502; 95% CI: 0.42513162, 0.93055788; P = 0.02033345] and 2 genus [Butyricicoccus: OR: 0.41432215; 95% CI: 0.22716865, 0.75566257; P = 0.0040564; Lactobacillus: OR: 0.6663767; 95% CI: 0.45679511, 0.97211616; P = 0.03513627].

CONCLUSIONS

Our findings offered compelling evidence of a causal association between gut microbiota and cirrhosis in European population and identified specific bacteria taxa that may regulate the genesis and progression of liver fibrosis and cirrhosis, may offer a new direction for the treatment of cirrhosis.

Gut microbiota and metabolic modulation by supplementation of polysaccharide-producing Bacillus licheniformis from Tibetan Yaks: A comprehensive multi-omics analysis

Gut microbiota and their metabolic processes depend on the intricate interplay of gut microbiota and their metabolic processes. Bacillus licheniformis, a beneficial food supplement, has shown promising effects on stabilizing gut microbiota and metabolites. However, the precise mechanisms underlying these effects remain elusive. In this study, we investigated the impact of polysaccharide-producing B. licheniformis as a dietary supplement on the gut microbiome and metabolites through a combination of scanning electron microscopy (SEM), histological analysis, high-throughput sequencing (HTS), and metabolomics. Our findings revealed that the B. licheniformis-treated group exhibited significantly increased jejunal goblet cells. Moreover, gut microbial diversity was lower in the treatment group as compared to the control, accompanied by noteworthy shifts in the abundance of specific bacterial taxa. Enrichment of Firmicutes, Lachnospiraceae, and Clostridiales_bacterium contrasted with reduced levels of Campylobacterota, Proteobacteria, Parasutterella, and Helicobacter. Notably, the treatment group showed significant weight gain after 33 days, emphasizing the polysaccharide's impact on host metabolism. Delving into gut metabolomics, we discovered significant alterations in metabolites. Nine metabolites, including olprinone, pyruvic acid, and 2-methyl-3-oxopropanoate, were upregulated, while eleven, including defoslimod and voclosporin were down-regulated, shedding light on phenylpropanoid biosynthesis, tricarboxylic acid cycle (TCA cycle), and the glucagon signaling pathway. This comprehensive multi-omics analysis offers compelling insights into the potential of B. licheniformis as a dietary polysaccharide supplement for gut health and host metabolism, promising significant implications for gut-related issues.

Wedelolactone alleviates cholestatic liver injury by regulating FXR-bile acid-NF-κB/NRF2 axis to reduce bile acid accumulation and its subsequent inflammation and oxidative stress

BACKGROUND

Cholestatic liver diseases (CLD) comprise a variety of disorders of bile formation, which causes chronic exposure to bile acid (BA) in the liver generally and results in hepatotoxicity and progressive hepatobiliary injury. Wedelolactone (7-methoxy-5, 11, 12-trihydroxy-coumestan, WED), the natural active compound derived from Ecliptae Herba, has been reported with valuable bioactivity for liver protection. Nevertheless, the effect of WED on cholestatic liver injury (CLI) remains unexplored.

PURPOSE

The present study aims to elucidate the protective effect of WED on Alpha-naphthylisothiocyanate (ANIT)-induced CLI mice, and to investigate its potential pharmacological mechanism.

METHODS

The anit-cholestatic and hepatoprotective effects of WED were evaluated in ANIT-induced CLI mice. Non-targeted metabolomics study combined with ingenuity pathway analysis (IPA) was used to explore the key mechanism of WED. The BA metabolic profile in enterohepatic circulation was analyzed to evaluate the effect of WED in regulating BA metabolism. Furthermore, molecular dynamics (MD) simulation and cellular thermal shift assay (CETSA) were used to simulate and verify the targeting activation of WED on the Farnesoid X receptor (FXR). The core role of FXR in WED promoting BA transportation, and alleviating BA accumulation-induced hepatotoxicity was further evaluated in WT and FXR knockout mice or hepatocytes.

RESULTS

WED dose-dependently alleviated ANIT-induced cholestasis and liver injury in mice, and simultaneously suppressed the signaling pathway of nuclear factor-kappa B/nuclear factor-erythroid 2-related factor 2 (NF-κB/NRF2) to relieve inflammation and oxidative stress. At the metabolite level, WED improved the metabolic disorder in CLI mice focusing on the metabolism of BA, arachidonic acid, and glycerophospholipid, that closely related to the process of BA regulation, inflammation, and oxidative damage. WED targeting activated FXR, which then transcribed its target genes, including the bile salt export pump (BSEP) and the BA transporter, and subsequently increased BA transportation to restore the damaged enterohepatic circulation of BA. Meanwhile, WED alleviated hepatic BA accumulation and protected the liver from BA-induced damage via NF-κB/NRF2 signaling pathway. Furthermore, FXR deficiency suppressed the protective effect of WED in vitro and in vivo.

CONCLUSION

WED regulated BA metabolism and alleviated hepatic damage in cholestasis. It protected the liver according to adjusted BA transportation and relieved BA accumulation-related hepatotoxicity via FXR-bile acid-NF-κB/NRF2 axis. Our study provides novel insights that WED might be a promising strategy for cholestatic liver disease.

Potential role of bile acids in the pathogenesis of necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is one of the most common acute gastrointestinal diseases in preterm infants. Recent studies have found that NEC is not only caused by changes in the intestinal environment but also by the failure of multiple systems and organs, including the liver. The accumulation of bile acids (BAs) in the ileum and the disorder of ileal BA transporters are related to the ileum injury of NEC. Inflammatory factors such as tumor necrosis factor (TNF)-α and interleukin (IL)-18 secreted by NEC also play an important role in regulating intrahepatic BA transporters. As an important link connecting the liver and intestinal circulation, the bile acid metabolic pathway plays an important role in the regulation of intestinal microbiota, cell proliferation, and barrier protection. In this review, we focus on how bile acids explore the dynamic changes of bile acid metabolism in necrotizing enterocolitis and the potential therapeutic value of targeting the bile acid signaling pathways.

Bile acids, gut microbiota, and therapeutic insights in hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is a prevalent and aggressive liver malignancy. The interplay between bile acids (BAs) and the gut microbiota has emerged as a critical factor in HCC development and progression. Under normal conditions, BA metabolism is tightly regulated through a bidirectional interplay between gut microorganisms and BAs. The gut microbiota plays a critical role in BA metabolism, and BAs are endogenous signaling molecules that help maintain liver and intestinal homeostasis. Of note, dysbiotic changes in the gut microbiota during pathogenesis and cancer development can disrupt BA homeostasis, thereby leading to liver inflammation and fibrosis, and ultimately contributing to HCC development. Therefore, understanding the intricate interplay between BAs and the gut microbiota is crucial for elucidating the mechanisms underlying hepatocarcinogenesis. In this review, we comprehensively explore the roles and functions of BA metabolism, with a focus on the interactions between BAs and gut microorganisms in HCC. Additionally, therapeutic strategies targeting BA metabolism and the gut microbiota are discussed, including the use of BA agonists/antagonists, probiotic/prebiotic and dietary interventions, fecal microbiota transplantation, and engineered bacteria. In summary, understanding the complex BA-microbiota crosstalk can provide valuable insights into HCC development and facilitate the development of innovative therapeutic approaches for liver malignancy.

The protective effect of forsythiaside A on 3,5-diethoxycarbonyl-1,4-dihydrocollidine-induced cholestatic liver injury in mice: Based on targeted metabolomics and molecular biology technology

Cholestasis is a disorder of bile secretion and excretion caused by a variety of etiologies. At present, there is a lack of functional foods or drugs that can be used for intervention. Forsythiaside A (FTA) is a natural phytochemical component isolated from the medicinal plant Forsythia suspensa (Thunb.) Vahl, which has a significant hepatoprotective effect. In this study, we investigated whether FTA could alleviate liver injury induced by cholestasis. In vitro, FTA reversed the decrease in viability of human intrahepatic bile duct epithelial cells, the decrease in antioxidant enzymes (SOD1, CAT and GSH-Px), and cell apoptosis induced by lithocholic acid. In vivo, FTA protected mice from 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC)-induced liver injury, abnormal serum biochemical indexes, abnormal bile duct hyperplasia, and inflammatory infiltration. Furthermore, FTA treatment alleviated liver fibrosis by inhibiting collagen deposition and HSC activation. The metabonomic results showed that DDC-induced bile acid disorders in the liver and serum were reversed after FTA treatment, which may benefit from the activation of the FXR/BSEP axis. In addition, FTA treatment increased the levels of antioxidant enzymes in the serum and liver. Meanwhile, FTA treatment inhibited ROS and MDA levels and cleaved caspase 3 protein expression, thereby reducing DDC-induced hepatic oxidative stress and apoptosis. Further studies showed that the antioxidant effects of FTA were dependent on the activation of the BRG1/NRF2/HO-1 axis. In a word, FTA has a significant hepatoprotective effect on cholestatic liver injury, and can be further developed as a functional food or drug to prevent and treat cholestatic liver injury.

The level of serum total bile acid is related to atherosclerotic lesions, prognosis and gut Lactobacillus in acute coronary syndrome patients

BACKGROUND

Bile acids play crucial roles in various metabolisms, as well as Lactobacillus in the intestine. But studies on their roles in acute coronary syndrome (ACS) are still insufficient. The aim of this study was to investigate their role and potential association with the severity of coronary lesions and the prognosis of ACS.

METHODS

Three hundred and sixty ACS patients were selected. Detection of gut Lactobacillus levels was done through 16S rDNA sequence analysis. Evaluation of the extent of lesions was done using the SYNTAX (SS) score. Mediation analysis was used to assess the relationship between serum total bile acid (TBA), Lactobacillus, atherosclerotic lesions and prognosis of ACS.

RESULTS

Logistic regressive analysis disclosed that serum TBA and Lactobacillus were independent predictors of coronary lesions (high vs. low SS: serum TBA adjusted odds ratio (aOR) = 0.8, 95% confidence interval (CI): 0.6-0.9, p < .01; Lactobacillus: aOR = 0.9, 95% CI: 0.9-1.0, p = .03). According to multivariate Cox regression analysis, they were negatively correlated with the overall risk of all-cause death (serum TBA: adjusted hazard ratio (aHR) = 0.1, 95% CI: 0.0-0.6, p = .02; Lactobacillus: aHR = 0.6, 95% CI: 0.4-0.9, p = .01), especially in acute myocardial infarction (AMI) but not in unstable angina pectoris (UAP). Ulteriorly, mediation analysis showed that serum TBA played an important role as a mediation effect in the following aspects: Lactobacillus (17.0%, p < .05) → SS association (per 1 standard deviation (SD) increase), Lactobacillus (43.0%, p < .05) → all-cause death (per 1 SD increase) and Lactobacillus (45.4%, p < .05) → cardiac death (per 1 SD increase).

CONCLUSIONS

The lower serum TBA and Lactobacillus level in ACS patients, especially in AMI, was independently linked to the risk of coronary lesions, all-cause death and cardiac death. In addition, according to our mediation model, serum TBA served as a partial intermediate in predicting coronary lesions and the risk of death by Lactobacillus, which is paramount to further exploring the mechanism of Lactobacillus and bile acids in ACS.KEY MESSAGESLower level of serum total bile acid (TBA) was highly associated with the severity of coronary lesions, myocardial damage, inflammation and gut Lactobacillus in acute coronary syndrome (ACS) patients, especially in acute myocardial infarction (AMI).Lower level of serum TBA was highly associated with mortality (including all-cause death and cardiac death) in patients with ACS, especially with AMI.Serum TBA had a partial mediating effect rather than regulating effect between gut Lactobacillus and coronary lesions and prognosis of ACS.

Probiotic Pediococcus pentosaceus Li05 Improves Cholestasis through the FXR-SHP and FXR-FGF15 Pathways

Primary sclerosing cholangitis (PSC), a rare chronic cholestatic liver disease, is characterized by intrahepatic or extrahepatic strictures accompanied by biliary fibrosis. So far, there are no effective therapies to slow down the progression of this disease. Farnesoid X receptors (FXRs) are ligand-activated transcription factors involved in the control of bile acid (BA) synthesis and enterohepatic circulation. Therefore, targeting FXRs holds promise as a potential approach for treating PSC. Pediococcus pentosaceus Li05 is a probiotic that was isolated from healthy volunteers and has previously been shown to have an anti-inflammatory effect in DSS-induced colitis. In this study, we established a 3,5-diethoxycarbonyl-1,4-Dihydrocollidine (DDC)-induced cholestasis mouse model and investigated the effects of Pediococcus pentosaceus Li05 on PSC. Our findings revealed that administration of Li05 significantly attenuated liver damage, hepatic inflammation, and fibrosis, as well as bile duct hyperplasia. Li05 activated the hepatic FXR-SHP and ileal FXR-FGF15 signaling pathways to decrease the expression of Cyp7a1. In addition, the Li05-modulated gut microbiota structure especially improved the abundance of 7α-dehydroxylation bacteria like Eubacterium. The intervention of Li05 also improved the intestinal barrier and reduced bacterial endotoxin translocation. Based on these findings, Li05 shows promise for future application as a therapeutic strategy for cholestasis.

Dual roles of nanocrystalline cellulose extracted from jute (Corchorus olitorius L.) leaves in resisting antibiotics and protecting probiotics

Antibiotics can cure diseases caused by bacterial infections, but their widespread use can have some side effects, such as probiotic reduction. There is an urgent need for such agents that can not only alleviate the damage caused by antibiotics, but also maintain the balance of the gut microbiota. In this study, we first characterized the nanocrystalline cellulose (NCC) extracted from plant jute (Corchorus olitorius L.) leaves. Next, we evaluated the protective effect of jute NCC and cellulose on human model gut bacteria (Lacticaseibacillus rhamnosus and Escherichia coli) under antibiotic stress by measuring bacterial growth and colony forming units. We found that NCC is more effective than cellulose in adsorbing antibiotics and defending the gut bacteria E. coli. Interestingly, the low-dose jute NCC clearly maintained the balance of key gut bacteria like Snodgrassella alvi and Lactobacillus Firm-4 in bees treated with tetracycline and reduced the toxicity caused by antibiotics. It also showed a more significant protective effect on human gut bacteria, especially L. rhamnosus, than cellulose. This study first demonstrated that low-dose NCC performed satisfactorily as a specific probiotic to mitigate the adverse effects of antibiotics on gut bacteria.

Effect of gut flora mediated-bile acid metabolism on intestinal immune microenvironment

According to reports, gut microbiota and metabolites regulate the intestinal immune microenvironment. In recent years, an increasing number of studies reported that bile acids (BAs) of intestinal flora origin affect T helper cells and regulatory T cells (Treg cells). Th17 cells play a pro-inflammatory role and Treg cells usually act in an immunosuppressive role. In this review, we emphatically summarised the influence and corresponding mechanism of different configurations of lithocholic acid (LCA) and deoxycholic acid (DCA) on intestinal Th17 cells, Treg cells and intestinal immune microenvironment. The regulation of BAs receptors G protein-coupled bile acid receptor 1 (GPBAR1/TGR5) and farnesoid X receptor (FXR) on immune cells and intestinal environment are elaborated. Furthermore, the potential clinical applications above were also concluded in three aspects. The above will help researchers better understand the effects of gut flora on the intestinal immune microenvironment via BAs and contribute to the development of new targeted drugs.

Holistic view of heat acclimation alleviated intestinal lesion in mice with heat stroke based on microbiome-metabolomics analysis

The severity of heat stroke (HS) is associated with intestinal injury, which is generally considered an essential issue for HS. Heat acclimation (HA) is considered the best strategy to protect against HS. In addition, HA has a protective effect on intestinal injuries caused by HS. Considering the essential role of gut microbes in intestinal structure and function, we decided to investigate the potential protective mechanism of HA in reducing intestinal injury caused by HS. HA model was established by male C57BL/6J mice (5-6 weeks old, 17-19 g) were exposed at (34 ± 0.7)°C for 4 weeks to establish an animal HA model. The protective effect of HA on intestinal barrier injury in HS was investigated by 16S rRNA gene sequencing and nontargeted liquid chromatography-mass spectrometry (LC-MS) metabolomics. According to the experimental results, HA can change the composition of the gut microbiota, which increases the proportion of lactobacilli, faecal bacteria, and urinobacteria but decreases the proportion of deoxycholic acid. Moreover, HA can reduce liver and kidney injury and systemic inflammation caused by HS and reduce intestinal injury by enhancing the integrity of the intestinal barrier. In addition, HA regulates inflammation by inhibiting NF-κB signalling and increasing tight junction protein expression in HS mice. HA induces changes in the gut microbiota, which may enhance tight junction protein expression, thereby reducing intestinal inflammation, promoting bile acid metabolism, and ultimately maintaining the integrity of the intestinal barrier. In conclusion, HA induced changes in the gut microbiota. Among the gut microbiota, lactobacilli may play a key role in the potential protective mechanism of HA.

Mechanism of triterpenoids from Alismatis Rhizoma against liver fibrosis based on an integrated approach using network pharmacology, molecular docking, and luciferase assay

Protostane-type triterpenoids are antifibrotic nature components with unique structures in Alismatis Rhizoma. However, the underlying mechanisms of them against liver fibrosis are not well illustrated. The present study aims to study the targets and mechanisms of Alismatis Rhizoma triterpenes responsible for their antifibrotic effects by network pharmacology, molecular docking, and luciferase assay. As a result, six molecular targets responsible for the antifibrotic effects of alisols against liver fibrosis were uncovered by network pharmacology, among which the activation of farnesoid X receptor (FXR/NR1H4) was highlighted and further confirmed by molecular docking and luciferase assay. Our present study provides a scientific basis for treating liver fibrosis by using Alismatis Rhizoma, especially via the FXR activation effects of alisols.

Do gut microbiome-targeted therapies improve liver function in cirrhotic patients? A systematic review and meta-analysis

BACKGROUND AND AIM

Microbiome-targeted therapies (MTTs) are considered as promising interventions for cirrhosis, but the impact of gut microbiome modulation on liver function and disease severity has not been fully assessed. We comprehensively evaluated the efficacy of MTTs in patients with liver cirrhosis.

METHODS

Data from randomized controlled trials were collected through MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, and ClinicalTrial.gov from inception to February 20, 2023. Clinical outcomes were pooled and expressed in terms of risk ratios or mean differences (MD). Additional subgroup and sensitivity analyses were performed to validate the robustness of findings. A trial sequential analysis was applied to calculate the required information size and evaluate the credibility of the meta-analysis results.

RESULTS

Twenty-one studies with a total of 1699 cirrhotic patients were included for meta-analysis. MTTs were associated with a significant reduction in aspartate aminotransferase (MD, -3.62; 95% CI, -6.59 to -0.65), the risk of hepatic encephalopathy (risk ratio = 0.56, 95% CI: 0.46 to 0.68), model for end-stage liver disease score (MD, -0.90; 95% CI, -1.17 to -0.11), ammonia (MD, -11.86; 95% CI, -16.39 to -7.33), and endotoxin (MD, -0.14; 95% CI, -0.23 to -0.04). The trial sequential analysis yielded reliable results of these outcomes. No effects were observed on the changes of other hepatic function indicators.

CONCLUSION

MTTs appeared to be associated with a slowed deterioration in liver cirrhosis, which could provide reference for clinicians in treatment of cirrhotic patients based on their conditions.

Emerging nanotherapeutic strategies targeting gut-X axis against diseases

Gut microbiota can coordinate with different tissues and organs to maintain human health, which derives the concept of the gut-X axis. Conversely, the dysbiosis of gut microbiota leads to the occurrence and development of various diseases, such as neurological diseases, liver diseases, and even cancers. Therefore, the modulation of gut microbiota offers new opportunities in the field of medicines. Antibiotics, probiotics or other treatments might restore unbalanced gut microbiota, which effects do not match what people have expected. Recently, nanomedicines with the high targeting ability and reduced toxicity make them an appreciative choice for relieving disease through targeting gut-X axis. Considering this paradigm-setting trend, the current review summarizes the advancements in gut microbiota and its related nanomedicines. Specifically, this article introduces the immunological effects of gut microbiota, summarizes the gut-X axis-associated diseases, and highlights the nanotherapeutics-mediated treatment via remolding the gut-X axis. Moreover, this review also discusses the challenges in studies related to nanomedicines targeting the gut microbiota and offers the future perspective, thereby aiming at charting a course toward clinic.

Farnesoid X receptor activation is required for the anti-inflammatory and anti-oxidative stress effects of Alisol B 23-acetate in carbon tetrachloride-induced liver fibrosis in mice

Previous studies have shown that Alisol B 23-acetate (23ABA) had potent liver-protection effects, however, its roles and potential mechanisms in carbon tetrachloride (CCl4)-induced liver fibrosis remain to be determined. The present study aimed to investigate the effects of 23ABA on CCl4-induced liver fibrosis and tried to elucidate the underlying mechanisms by focusing on regulating of farnesoid X receptor (FXR). In vivo study found that 23ABA alleviated the CCl4-induced liver injury, and showed no obvious systemic toxicity on mice. 23ABA inhibited the collagen production, decreased sera levels of hyaluronic acid (HA) and procollagen type III (PC-III), lowered mRNA expression of α-smooth muscle actin (α-SMA), fibronectin, collagen I and collagen III in livers of mice. 23ABA inhibited the mRNA expressions and the sera levels of interleukin-6 (IL-6), IL-1β, and tumor necrosis factor-α (TNF-α), as well as decreased the expression of cyclooxygenase 2 (COX-2) in fibrotic livers of mice. Besides, 23ABA decreased levels of reactive oxygen species (ROS) and malondialdehyde (MDA), increased glutathione (GSH) level, enhanced activities of superoxide dismutase (SOD) and glutathione reductase (GR) as well as increased mRNA expression of nuclear factor-E2-related factor 2 (Nrf2), glutamate-cysteine ligase, catalytic subunit (GCLC) and glutamate-cysteine ligase, modifier subunit (GCLM). Further study showed that the anti-liver injury and anti-fibrotic effects of 23ABA were abrogated by FXR antagonist guggulsterone (GS) in vivo. In addition, the inhibition effects of 23ABA on liver inflammation and oxidative stress were also weakened by treatment with GS in CCl4-induced fibrotic mice livers. In conclusion, the protective effects of 23ABA against CCl4-induced liver injury and fibrosis, due to FXR-mediated regulation of liver inflammation and oxidative stress.