Pharmacokinetic Characteristics of Baicalin in Rats with 17α-ethynyl-estradiol-induced Intrahepatic Cholestasis

Baicalin methyl ester prevents the LPS - induced mice intestinal barrier damage in vivo and in vitro via P65/TNF-α/MLCK/ZO-1 signal pathway

The effect of baicalin methyl ester (BME) on the regulation of mice intestinal barrier in the inflammatory response was studied in vivo and in vitro. Thirty six C57/BL mice were randomly divided into six groups (n = 6): control group; LPS group (LPS 3.5 mg/kg given intraperitoneal [ip] on day 7 of the study only), PBS group, and three BME groups (low: 50 mg/kg; medium: 100 mg/kg; high: 200 mg/kg) orally dosed with BME for 7d and LPS ip on day 7. All mice were sacrificed on day 8, and jejunum tissue collected for histopathology (H&E and PAS staining), protein expression of pro-inflammatory factors (TNF-α, IL-6, IL-8, IFN-γ) by ELISA, and intestinal tight junction proteins (ZO-1, occludin, claudin-1 and claudin-4) by Western Blot. Compared with the control group, LPS significantly increased the serum cytokines DAO (p < 0.01) and DLA (p < 0.01), upregulated the expression of pro-inflammatory factors, MLCK proteins (p <0.05) and increased the MLCK/ZO-1ratio (p <0.001). LPS also decreased the expression of claudin-4 (p < 0.01) in the jejunum and induced an inflammatory response damaging the jejunal mucosal barrier. Pretreatment with BME (100-200 mg/kg) significantly decreased the cytokines DAO (p < 0.05) and DLA (p < 0.01) in the serum, pro-inflammatory factors in the jejunum, significantly down-regulated the expression of MLCK (p <0.05) and the ratio of MLCK/ZO-1(p <0.001) but upregulated the expressions of ZO-1(p < 0.01), occludin (p < 0.05), claudin-1(p < 0.05) and claudin-4 (p < 0.05), and thereby restored the intestinal tissue structure, suggestive of alleviation of LPS-induced intestinal inflammation by BME. In vitro, MODE-K cells (derived from mice intestinal epithelium) were exposed to BME at 0 (control group-No LPS), 10, 20 and 40 μM BME for 24 h prior to LPS addition at 50 μg/mL for 2 h. LPS significantly increased the expression of pro-inflammatory factors, MLCK (p < 0.01) and the ratio of MLCK/ZO-1(p <0.001), decreased the expressions of ZO-1 (p < 0.05), occludin (p < 0.01), claudin-1 (p < 0.01) and claudin-4 (p < 0.01) in MODE-K cells compared with the control group. Compared with the LPS group, BME (10 - 40 μM) significantly decreased the expression of pro-inflammatory factors, MLCK (p < 0.05) and the ratio of MLCK/ZO-1(p <0.01) but increased the expressions of ZO-1(p < 0.01), occludin (p < 0.05) and claudin-4(p < 0.01) indicating an up-regulation of the expression of tight junction proteins by BME. On addition of extrinsic TNF-α plus LPS, the TNF- α level increased (p < 0.001) in MODE-K cells and the protein expression of MLCK (p < 0.01) was markedly up-regulated. Molecular docking predicted BME interacted with P65 by forming hydrogen bonds. IP-WB further confirmed that BME was directly bound to P65 protein in MODE-K cells. In conclusion, BME was able to restore the intestinal barrier through the P65 / TNF-α / MLCK / ZO-1 signaling pathway.

Drug disposition in cholestasis: An important concern

Cholestasis, a chronic liver condition, disrupts bile acid homeostasis and complicates drug disposition, posing significant challenges in medicating cholestatic patients. Drug metabolism enzymes and transporters (DMETs) are pivotal in drug clearance. Research indicates that cholestasis leads to alterations in both hepatic and extrahepatic DMETs, with changes in expression and function documented in rodents and humans. This review synthesizes the modifications in key drug disposition components within cholestasis, focusing on cytochrome P450 (CYP450), drug transporters, and their substrates. Additionally, we briefly discuss certain drugs that have demonstrated efficacy in restoring DMET expression in cholestatic conditions. Ultimately, these insights necessitate a reevaluation of drug selection and dosing guidelines for patients with cholestasis.

Baicalin inhibits apoptosis and enhances chondrocyte proliferation in thiram-induced tibial dyschondroplasia in chickens by regulating Bcl-2/Caspase-9 and Sox-9/Collagen-II expressions

Avian tibial dyschondroplasia (TD) is a skeletal disease affecting fast growing chickens, resulting in non-mineralized avascular cartilage. This metabolic disorder is characterized by lameness and reduced growth performance causing economic losses. The aim of this study was to investigate the protective effects of baicalin against TD caused by thiram exposure. A total of two hundred and forty (n = 240) one day-old broiler chickens were uniformly and randomly allocated into three different groups (n = 80) viz. control, TD, and baicalin groups. All chickens received standard feed, however, to induce TD, the TD and baicalin groups received thiram (tetramethylthiuram disulfide) at a rate of 50 mg/kg feed from days 4-7. The thiram induction in TD and baicalin groups resulted in lameness, high mortality, and enlarged growth-plate, poor production performance, reduction in ALP, GSH-Px, SOD, and T-AOC levels, and increased AST and ALT, and MDA levels. Furthermore, histopathological results showed less vascularization, and mRNA and protein expression levels of Sox-9, Col-II, and Bcl-2 showed significant downward trend, while caspase-9 displayed significant up-regulation in TD-affected chickens. After the TD induction, the baicalin group was orally administered with baicalin at a rate of 200 mg/kg from days 8-18. Baicalin administration increased the vascularization, and chondrocytes with intact nuclei, alleviated lameness, decreased GP size, increased productive capacity, and restored the liver antioxidant enzymes and serum biochemical levels. Furthermore, baicalin significantly up-regulated the gene and protein expressions of Sox-9, Col-II, and Bcl-2, and significantly down-regulated the expression of caspase-9 (p < 0.05). Therefore, the obtained results suggest that baicalin could be a possible choice in thiram toxicity alleviation by regulating apoptosis and chondrocyte proliferation in thiram-induced tibial dyschondroplasia.

Consecutive baicalin treatment relieves its accumulation in rats with intrahepatic cholestasis by increasing MRP2 expression

Baicalin, an important flavonoid isolated from Scutellaria baicalensis Georgi, is a Chinese herb widely used in clinical practice. We previously reported the in vivo accumulation of baicalin in rats with intrahepatic cholestasis (IHC) after a single dose. However, the effects of the long-term administration of baicalin on its pharmacokinetics are unknown. Thus, we investigated the disposition of baicalin in normal rats and those with IHC after single and multiple consecutive administrations. In addition, we further investigated the effect of baicalin on multidrug resistance protein 2 (MRP2) in vivo to explore the underlying mechanism. In our study, the liquid chromatography-mass spectrometry (LC-MS) method established to determine baicalin concentrations in rat blood was simple, specific, and with linearity (R² = 0.9980) in the range of 1.01-506.00 μg/mL. The relative standard deviations (RSD) for intra-day and inter-day precision were not more than 10.55%, and the intra-day and inter-day accuracies were 94.94%-109.13%. The recovery rate and stability were in line with the requirements of the quantitative analysis of biological samples as stated in the Chinese Pharmacopoeia (2020 Edition). Compared with that in normal rats, the C_max and t_1/2 increased significantly in EE-induced rats with IHC, whereas the clearance (CL) decreased after a single administration of baicalin. However, the area under the curve decreased, CL increased, and the t_1/2 was shortened after the continuous administration of baicalin in the IHC rat model compared with the single administration of baicalin, and the pharmacokinetic characteristics were similar to those in normal rats. Moreover, MRP2 expression increased in rats with IHC with the continuous administration of baicalin. Continuous baicalin intervention could effectively reduce its accumulation in rats with IHC, and the mechanism may be attributed to its enhancement of MRP2 expression.

The water extract of Radix scutellariae, its total flavonoids and baicalin inhibited CYP7A1 expression, improved bile acid, and glycolipid metabolism in T2DM mice

ETHNOPHARMACOLOGICAL RELEVANCE

Radix scutellariae (the root of Scutellaria baicalensis Georgi), is a traditional Chinese medicine (TCM) used to treat type 2 diabetes mellitus (T2DM). Abundant flavonoids are the antidiabetic components of Radix scutellariae, of which baicalin (Baicalein 7-O-glucuronide, BG) is the major bioactive component. Our previous studies found that the water extract of Radix scutellariae (WESB) could exert hypoglycemic and hypolipidemic efficacies by adjusting the ileum FXR-medicated interaction between gut microbiota and bile acid (BA) metabolism. However, it remains unclear whether WESB and its biologically active ingredients exert an antidiabetic effect through bile acid signaling mediated by FXR-CYP7A1.

AIMS OF THE STUDY

To explore the mechanism of WESB and its total flavonoids (TF) further and BG on BA signals and glycolipid metabolism in T2DM mice.

MATERIALS AND METHODS

The antidiabetic effects of WESB, TF and BG were evaluated by indexing the body weight, fasting blood glucose (FBG) and oral glucose tolerance test (OGTT) in HFD/STZ-induced (high-fat diet and streptozocin) diabetic mice, and comparing them with the positive control (metformin). The lipids in the mouse liver and the total bile acids (TBA) in the mouse liver and bile were detected by commercial kits. The concentration of BAs in the mouse feces was determined by liquid chromatography-tandem mass spectrometry. The protein expression levels of cholesterol 7α-hydroxylase (CYP7A1), farnesol X receptor (FXR), etc., in the liver and/or ileum, play a key role in the BAs metabolism of T2DM mice were evaluated by immunoblot analysis.

RESULTS

The hyperglycemia and impaired glucose tolerance of T2DM mice were improved after WESB, TF and BG treatment. Especially after BG administration, the levels of low-density lipoprotein-cholesterol (LDL-c) and total glyceride (TG) in the T2DM mouse liver were significantly decreased (p < 0.05). While the level of high-density lipoprotein cholesterol (HDL-c) was significant increased (p < 0.001). Meanwhile, the levels of TBA in both the liver and bile of T2DM mice were significantly decreased by BG (p < 0.05). Moreover, the high expression of CYP7A1 in the liver of T2DM mice was significantly inhibited by WESB, TF and BG (p < 0.05), and the high expression of FXR in the ileum of T2DM mice was significantly inhibited by TF (p < 0.05).

CONCLUSION

These results indicated that the hypoglycemic effects of WESB, TF and BG might be exerted by inhibiting the expression of CYP7A1 in T2DM mice, and TF inhibited expression of intestinal FXR by inducing changes in fecal BA profile. BG significantly improved hepatic lipid metabolism. Moreover, BG reduced lipid accumulation in the liver and bile by inhibiting the expression of CYP7A1 in T2DM mice. These findings provide useful explanations for the antidiabetic mechanism of Radix scutellariae.

Role of baicalin as a potential therapeutic agent in hepatobiliary and gastrointestinal disorders: A review

Baicalin is a natural bioactive compound derived from Scutellaria baicalensis, which is extensively used in traditional Chinese medicine. A literature survey demonstrated the broad spectrum of health benefits of baicalin such as antioxidant, anticancer, anti-inflammatory, antimicrobial, cardio-protective, hepatoprotective, renal protective, and neuroprotective properties. Baicalin is hydrolyzed to its metabolite baicalein by the action of gut microbiota, which is further reconverted to baicalin via phase 2 metabolism in the liver. Many studies have suggested that baicalin exhibits therapeutic potential against several types of hepatic disorders including hepatic fibrosis, xenobiotic-induced liver injury, fatty liver disease, viral hepatitis, cholestasis, ulcerative colitis, hepatocellular and colorectal cancer. During in vitro and in vivo examinations, it has been observed that baicalin showed a protective role against liver and gut-associated abnormalities by modifying several signaling pathways such as nuclear factor-kappa B, transforming growth factor beta 1/SMAD3, sirtuin 1, p38/mitogen-activated protein kinase/Janus kinase, and calcium/calmodulin-dependent protein kinase kinaseβ/adenosine monophosphate-activated protein kinase/acetyl-coenzyme A carboxylase pathways. Furthermore, baicalin also regulates the expression of fibrotic genes such as smooth muscle actin, connective tissue growth factor, β-catenin, and inflammatory cytokines such as interferon gamma, interleukin-6 (IL-6), tumor necrosis factor-alpha, and IL-1β, and attenuates the production of apoptotic proteins such as caspase-3, caspase-9 and B-cell lymphoma 2. However, due to its low solubility and poor bioavailability, widespread therapeutic applications of baicalin still remain a challenge. This review summarized the hepatic and gastrointestinal protective attributes of baicalin with an emphasis on the molecular mechanisms that regulate the interaction of baicalin with the gut microbiota.

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

BACKGROUND

Our previous clinical research showed that the interaction between gut microbiota and bile acids (BAs) in patients with type 2 diabetes mellitus (T2DM) changed significantly. We hypothesized that T2DM could be improved by adjusting this interaction mediated by farnesoid X receptor (FXR). T2DM belongs to the category of "xiaoke" in traditional Chinese medicine. Radix scutellariae has the effects of clearing away heat and eliminating dampness, curing jaundice and quenching thirst and is widely used alone or in combination with other medicines for the treatment of T2DM in China and throughout Asia. Additionally, the interaction between Radix scutellariae and gut microbiota may influence its efficacy in the treatment of T2DM.

PURPOSE

This study chose Radix scutellariae to validate that T2DM could improve by adjusting the interaction between gut microbiota and bile acid metabolism.

STUDY DESIGN AND METHODS

Radix scutellariae water extract (WESB) was administered to a T2DM rat model established by a high-fat diet combined with streptozotocin. The body weight and blood glucose and insulin levels were measured. The levels of serum lipids, creatinine, uric acid, albumin and total bile acid were also detected. Changes in the pathology and histology of the pancreas, liver and kidney were observed by haematoxylin-eosin staining. The 16S rRNAs of gut microbiota were sequenced, and the faecal and serum BAs were determined by liquid chromatography tandem mass spectrometry. The expression levels of BA metabolism-associated proteins in the liver and intestine were evaluated by immunoblot analysis.

RESULTS

The results showed that WESB improved hyperglycaemia, hyperlipaemia, and liver and kidney damage in T2DM rats. In addition, the abundances of key gut microbiota and the concentrations of certain secondary BAs in faeces and serum were restored. Moreover, there was a significant correlation between the restored gut microbiota and BAs, which might be related to the activation of liver cholesterol 7α-hydroxylase (CYP7A1) and the inhibition of FXR expression in the intestine rather than the liver.

CONCLUSIONS

This study provided new ideas for the prevention or treatment of clinical diabetes and its complications by adjusting the interaction between gut microbiota and bile acid metabolism.

Pharmacological properties of baicalin on liver diseases: a narrative review

Baicalin is the main active component of Scutellaria baicalensis, widely used in traditional Chinese medicine thanks to its various pharmacological effects, such as anti-tumor, anti-inflammatory, and antibacterial properties, as well as cardiovascular, hepatic, and renal protective effect. Recently, the protective effects of baicalin on liver disease have received much more attention. Several studies showed that baicalin protects against several types of liver diseases including viral hepatitis, fatty liver disease, xenobiotic induced liver injury, cholestatic liver injury, and hepatocellular carcinoma, with a variety of pharmacological mechanisms. A comprehensive understanding of the mechanism of baicalin can provide a valuable reference for its clinical use, but up to now, no narrative review is available that summarizes the pharmacological effects of baicalin to clarify its potential use in the treatment of liver diseases. Therefore, this review summarizes the progress of baicalin research and the underlying mechanism in the treatment of various liver diseases, to promote further research and its clinical application.

Baicalin and the liver-gut system: Pharmacological bases explaining its therapeutic effects

With the development of high-throughput screening and bioinformatics technology, natural products with a range of pharmacological targets in multiple diseases have become important sources of new drug discovery. These compounds are derived from various plants, including the dried root of Scutellaria baicalensis Georgi, which is often used as a traditional Chinese herb named Huangqin, a popular medication used for thousands of years in China. Many studies have shown that baicalin, an extract from Scutellaria baicalensis Georgi, exerts various protective effects on liver and gut diseases. Baicalin plays a therapeutic role mainly by mediating downstream apoptosis and immune response pathways induced by upstream oxidative stress and inflammation. During oxidative stress regulation, PI3K/Akt/NRF2, Keap-1, NF-κB and HO-1 are key factors associated with the healing effects of baicalin on NAFLD/NASH, ulcerative colitis and cholestasis. In the inflammatory response, IL-6, IL-1β, TNF-α, MIP-2 and MIP-1α are involved in the alleviation of NAFLD/NASH, cholestasis and liver fibrosis by baicalin, as are TGF-β1/Smads, STAT3 and NF-κB. Regarding the apoptosis pathway, Bax, Bcl-2, Caspase-3 and Caspase-9 are key factors related to the suppression of hepatocellular carcinoma and attenuation of liver injury and colorectal cancer. In addition to immune regulation, PD-1/PDL-1 and TLR4-NF-κB are correlated with the alleviation of hepatocellular carcinoma, ulcerative colitis and colorectal cancer by baicalin. Moreover, baicalin regulates intestinal flora by promoting the production of SCFAs. Furthermore, BA is involved in the interactions of the liver-gut axis by regulating TGR5, FXR, bile acids and the microbiota. In general, a comprehensive analysis of this natural compound was conducted to determine the mechanism by which it regulates bile acid metabolism, the intestinal flora and related signaling pathways, providing new insights into the pharmacological effects of baicalin. The mechanism linking the liver and gut systems needs to be elucidated to draw attention to its great clinical importance.

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

BACKGROUND AND AIMS

Cholestatic liver disease is characterized by gut dysbiosis and excessive toxic hepatic bile acids (BAs). Modification of gut microbiota and repression of BA synthesis are potential strategies for the treatment of cholestatic liver disease. The purpose of this study was to examine the effects and to understand the mechanisms of the probiotic Lactobacillus rhamnosus GG (LGG) on hepatic BA synthesis, liver injury, and fibrosis in bile duct ligation (BDL) and multidrug resistance protein 2 knockout (Mdr2-/- ) mice.

APPROACH AND RESULTS

Global and intestine-specific farnesoid X receptor (FXR) inhibitors were used to dissect the role of FXR. LGG treatment significantly attenuated liver inflammation, injury, and fibrosis with a significant reduction of hepatic BAs in BDL mice. Hepatic concentration of taurine-β-muricholic acid (T-βMCA), an FXR antagonist, was markedly increased in BDL mice and reduced in LGG-treated mice, while chenodeoxycholic acid, an FXR agonist, was decreased in BDL mice and normalized in LGG-treated mice. LGG treatment significantly increased the expression of serum and ileum fibroblast growth factor 15 (FGF-15) and subsequently reduced hepatic cholesterol 7α-hydroxylase and BA synthesis in BDL and Mdr2-/- mice. At the molecular level, these changes were reversed by global and intestine-specific FXR inhibitors in BDL mice. In addition, LGG treatment altered gut microbiota, which was associated with increased BA deconjugation and increased fecal and urine BA excretion in both BDL and Mdr2-/- mice. In vitro studies showed that LGG suppressed the inhibitory effect of T-βMCA on FXR and FGF-19 expression in Caco-2 cells.

CONCLUSION

LGG supplementation decreases hepatic BA by increasing intestinal FXR-FGF-15 signaling pathway-mediated suppression of BA de novo synthesis and enhances BA excretion, which prevents excessive BA-induced liver injury and fibrosis in mice.

Baicalin Protects Against 17α-Ethinylestradiol-Induced Cholestasis via the Sirtuin 1/Hepatic Nuclear Receptor-1α/Farnesoid X Receptor Pathway

Estrogen-induced cholestasis (EIC) is characterized by impairment of bile flow and accumulated bile acids (BAs) in the liver, always along with the liver damage. Baicalin is a major flavonoid component of Scutellaria baicalensis, and has been used in the treatment of liver diseases for many years. However, the role of baicalin in EIC remains to be elucidated. In this study, we demonstrated that baicalin showed obvious hepatoprotective effects in EIC rats by reducing serum biomarkers and increasing the bile flow rate, as well as by alleviating liver histology and restoring the abnormal composition of hepatic BAs. In addition, baicalin protected against estrogen-induced liver injury by up-regulation of the expression of hepatic efflux transporters and down-regulation of hepatic uptake transporters. Furthermore, baicalin increased the expression of hepatic BA synthase (CYP27A1) and metabolic enzymes (Bal, Baat, Sult2a1) in EIC rats. We showed that baicalin significantly inhibited hepatic inflammatory responses in EIC rats through reducing elevated levels of TNF-α, IL-1β, IL-6, and NF-κB. Finally, we confirmed that baicalin maintains hepatic BA homeostasis and alleviates inflammation through sirtuin 1 (Sirt1)/hepatic nuclear receptor-1α (HNF-1α)/farnesoid X receptor (FXR) signaling pathway. Thus, baicalin protects against estrogen-induced cholestatic liver injury, and the underlying mechanism involved is related to activation of the Sirt1/HNF-1α/FXR signaling pathway.

Natural products for the prevention and treatment of cholestasis: A review

Cholestasis is a common manifestation of decreased bile flow in various liver diseases. It results in fibrosis and even cirrhosis without proper treatment. It is believed that a wide range of factors, including transporter dysfunction, oxidative stress, inflammatory damage, and immune disruption, can cause cholestasis. In recent years, natural products have drawn much attention for specific multiple-target activities in diseases. Many attempts have been made to investigate the anticholestatic effects of natural products with advanced technology. This review summarizes recent studies on the biological activities and mechanisms of recognized compounds for cholestasis treatment. Natural products, including various flavonoids, phenols, acids, quinones, saponins, alkaloids, glycosides, and so on, function as comprehensive regulators via ameliorating oxidative stress, inflammation, and apoptosis, restoring bile acid balance with hepatic transporters, and adjusting immune disruption. Moreover, in this progress, nuclear factor erythroid 2-related factor 2, reactive oxygen species production, heme oxygenase-1, NF-κB, cholesterol 7 alpha-hydroxylase, and farnesoid X receptors are thought as main targets for the activity of natural products. Therefore, this review presents the detailed mechanisms that include multiple targets and diverse signalling pathways. Natural products are the valuable when seeking novel therapeutic agents to treat cholestatic liver diseases.

Pharmacokinetics of B-Ring Unsubstituted Flavones

B-ring unsubstituted flavones (of which the most widely known are chrysin, baicalein, wogonin, and oroxylin A) are 2-phenylchromen-4-one molecules of which the B-ring is devoid of any hydroxy, methoxy, or other substituent. They may be found naturally in a number of herbal products used for therapeutic purposes, and several have been designed by researchers and obtained in the laboratory. They have generated interest in the scientific community for their potential use in a variety of pathologies, and understanding their pharmacokinetics is important for a grasp of their optimal use. Based on a comprehensive survey of the relevant literature, this paper examines their absorption (with deglycosylation as a preliminary step) and their fate in the body, from metabolism to excretion. Differences among species (inter-individual) and within the same species (intra-individual) variability have been examined based on the available data, and finally, knowledge gaps and directions of future research are discussed.

Pharmacokinetics and Bioavailability Enhancement of Baicalin: A Review

Baicalin is one of the major bioactive components of Scutellaria radix, a Chinese herb that has been used since ancient times. Baicalin has various pharmacological activities, including antitumor, antimicrobial, and antioxidant, and has wide clinical applications. Baicalin displays a distinct pharmacokinetic profile including gastrointestinal hydrolysis, enterohepatic recycling, carrier-mediated transport, and complicated metabolism. The in vivo disposition of baicalin is affected by combinations of other herbs and baicalin can interact with other co-administered drugs due to competition between metabolic enzymes and protein binding. Furthermore, baicalin exhibits altered pharmacokinetic properties under different pathological conditions. Due to its low bioavailability, emerging novel baicalin preparations including nano/micro-scale baicalin delivery systems show better absorption and higher bioavailability in preclinical studies, and show promise for future clinical applications. Thus, this current review offers a comprehensive report on the pharmacokinetic behavior of baicalin and strategies to improve its bioavailability.

Calculus Bovis Sativus Improves Bile Acid Homeostasis via Farnesoid X Receptor-Mediated Signaling in Rats With Estrogen-Induced Cholestasis

Cholestatic diseases are characterized by toxic bile acid (BA) accumulation, and abnormal BA composition, which subsequently lead to liver injury. Biochemical synthetic Calculus Bovis Sativus (CBS) is derived from natural Calculus Bovis, a traditional Chinese medicine, which has been used to treat hepatic diseases for thousands of years. Although it has been shown that CBS administration to 17α-ethinylestradiol (EE)-induced cholestatic rats improves bile flow and liver injury, the involved underlying mechanism is largely unknown. In this study, we showed that CBS administration to EE-induced cholestatic rats significantly decreased serum and hepatic BA levels and reversed hepatic BA composition. DNA microarray analysis suggested that the critical pathways enriched by CBS treatment were bile secretion and primary BA synthesis. These findings led us to focus on the effects of CBS on regulating BA homeostasis, including BA transport, synthesis and metabolism. CBS enhanced hepatic BA secretion by inducing efflux transporter expression and inhibiting uptake transporter expression. Moreover, CBS reduced BA synthesis by repressing the expression of BA synthetic enzymes, CYP7A1 and CYP8B1, and increased BA metabolism by inducing the expression of metabolic enzymes, CYP3A2, CYP2B10, and SULT2A1. Mechanistic studies indicated that CBS increased protein expression and nuclear translocation of hepatic and intestinal farnesoid X receptor (FXR) to regulate the expression of these transporters and enzymes. We further demonstrated that beneficial effects of CBS administration on EE-induced cholestatic rats were significantly blocked by guggulsterone, a FXR antagonist. Therefore, CBS improved BA homeostasis through FXR-mediated signaling in estrogen-induced cholestatic rats. Together, these findings suggested that CBS might be a novel and potentially effective drug for the treatment of cholestasis.