Colesevelam has no acute effect on postprandial GLP-1 levels but abolishes gallbladder refilling.

OBJECTIVE: Colesevelam, a bile acid sequestrant approved for the treatment of hypercholesterolaemia, improves glycaemic control in type 2 diabetes. We hypothesised that single-dose colesevelam increases postprandial GLP-1 secretion, thus, reducing postprandial glucose excursions in individuals with type 2 diabetes. Further, we explored the effects of single-dose colesevelam on ultrasonography-assessed postprandial gallbladder motility, paracetamol absorption (proxy for gastric emptying), and circulating factors known to affect gallbladder motility. METHODS: In a randomised, double-blind, placebo-controlled crossover study, 12 individuals with type 2 diabetes (mean ± SD: age 61 ± 8.8 years; body mass index 29.8 ± 3.0 kg/m2) were subjected to 4 mixed meal tests on separate days; 2 with orally administered colesevelam (3.75 g) and 2 with placebo, with intravenous infusion of the GLP-1 receptor antagonist exendin(9-39)NH2 or saline. RESULTS: Single-dose colesevelam had no effect on postprandial concentrations of glucose (P = .786), C-peptide (P = .440), or GLP-1 (P = .729), and exendin(9-39)NH2 administration revealed no GLP-1-mediated effects of colesevelam. Colesevelam did not affect gallbladder emptying but abolished gallbladder refilling (P = .001), increased postprandial cholecystokinin (CCK) secretion (P = .010), and decreased postprandial serum concentrations of fibroblast growth factor 19 (FGF19) (P = .035) and bile acids (P = .043). CONCLUSION: Single-dose colesevelam had no effect on postprandial GLP-1 responses or glucose tolerance but disrupted postprandial gallbladder refilling by increasing CCK secretion and reducing circulating concentrations of FGF19 and bile acids. These findings leave the antidiabetic actions of colesevelam unresolved but provide mechanistic insights into its effect on gallbladder motility.

Oral SSTR5 Antagonist SCO-240 for Growth Hormone Stimulation: A Phase I Single-Dose Study in Healthy Individuals.

Somatostatin inhibits endocrine and exocrine secretion in various tissues by acting on five somatostatin receptor subtypes (SSTR1-5). The clinical effects of SSTR5 antagonism remain unknown. Herein, we evaluated the effects of SCO-240, an oral SSTR5 antagonist, in healthy individuals. This randomized, single-center, double-blind, placebo-controlled, phase I study included healthy Japanese and White individuals. The effects of ascending single oral doses of SCO-240 were evaluated in healthy individuals. The main outcome measures were safety, tolerability, pharmacokinetics, and pharmacodynamics (gallbladder contractions and levels of serum insulin and plasma glucagon-like peptide-1 (GLP-1)). The levels of pituitary hormones were evaluated in our exploratory analysis. The results indicated that SCO-240 was safe and well-tolerated at all tested doses. Oral SCO-240 was readily absorbed, with its systemic exposure increasing in a dose-dependent manner. The median time to maximum concentration and mean terminal half-life of SCO-240 were 3-4 and 10.2-12.6 hours, respectively, in the ascending dose section. No clinically meaningful changes in SCO-240 pharmacokinetic profiles were observed between fed and fasted or between Japanese and White individuals. No increase in gallbladder contractions or levels of insulin and GLP-1 were detected. SCO-240 induced robust growth hormone (GH) secretion without altering the levels of other pituitary hormones. In conclusion, the study is the first to demonstrate that SSTR5 antagonism stimulates GH secretion in humans. SCO-240 was safe and well-tolerated and exhibited once-daily oral dosing potential. The robust effects of SCO-240 on GH secretion suggest that it may be a treatment option for GH-related disorders.

Bile salt hydrolase acyltransferase activity expands bile acid diversity.

Bile acids (BAs) are steroid detergents in bile that contribute to the absorption of fats and fat-soluble vitamins while shaping the gut microbiome because of their antimicrobial properties1-4. Here we identify the enzyme responsible for a mechanism of BA metabolism by the gut microbiota involving amino acid conjugation to the acyl-site of BAs, thus producing a diverse suite of microbially conjugated bile acids (MCBAs). We show that this transformation is mediated by acyltransferase activity of bile salt hydrolase (bile salt hydrolase/transferase, BSH/T). Clostridium perfringens BSH/T rapidly performed acyl transfer when provided various amino acids and taurocholate, glycocholate or cholate, with an optimum at pH 5.3. Amino acid conjugation by C. perfringens BSH/T was diverse, including all proteinaceous amino acids except proline and aspartate. MCBA production was widespread among gut bacteria, with strain-specific amino acid use. Species with similar BSH/T amino acid sequences had similar conjugation profiles and several bsh/t alleles correlated with increased conjugation diversity. Tertiary structure mapping of BSH/T followed by mutagenesis experiments showed that active site structure affects amino acid selectivity. These MCBA products had antimicrobial properties, where greater amino acid hydrophobicity showed greater antimicrobial activity. Inhibitory concentrations of MCBAs reached those measured natively in the mammalian gut. MCBAs fed to mice entered enterohepatic circulation, in which liver and gallbladder concentrations varied depending on the conjugated amino acid. Quantifying MCBAs in human faecal samples showed that they reach concentrations equal to or greater than secondary and primary BAs and were reduced after bariatric surgery, thus supporting MCBAs as a significant component of the BA pool that can be altered by changes in gastrointestinal physiology. In conclusion, the inherent acyltransferase activity of BSH/T greatly diversifies BA chemistry, creating a set of previously underappreciated metabolites with the potential to affect the microbiome and human health.

Discovery of betulinic acid derivatives as gut-restricted TGR5 agonists: Balancing the potency and physicochemical properties.

The pleiotropic effects of TGR5 make it an appealing target for intervention of metabolic and inflammatory disorders, but systemic activation of TGR5 faces challenges of on-target side effects, especially gallbladder filling. Gut-restricted agonists were proved to be sufficient to circumvent these side effects, but extremely low systemic exposure may not be effective in activating TGR5 since it is located on the basolateral membrane. Herein, to balance potency and physicochemical properties, a series of gut-restricted TGR5 agonists with diversified kinetophores had been designed and synthesized. Compound 22-Na exhibited significant antidiabetic effect, and showed favorable gallbladder safety after 7 days of oral administration in humanized TGR5H88Y mice, confirming that gut-restricted agonism of TGR5 is a viable strategy to alleviate systemic target-related effects.

Therapeutic effect of yinchenhao decoction on cholelithiasis via mucin in the gallbladder and intestine.

Cholelithiasis is a common and frequently occurring disease worldwide that belongs to the category of jaundice in traditional Chinese medicine. Yinchenhao decoction (YD) consists of Artemisia capillaris Thunb., Gardenia jasminoides J.Ellis, and Rheum palmatum L., and is traditionally used to treat jaundice, which has a significant therapeutic effect on cholelithiasis. Our study aimed to investigate the pathological mechanism of cholelithiasis and the therapeutic mechanism of YD via mucin in the gallbladder and intestine. YD was prepared and analyzed using HPLC. The supersaturation stability experiment was designed by the solvent-shift method. The cell transport experiment was conducted by coculture monolayers. The animal experiment was performed using a cholelithiasis model with a high-cholesterol diet. The related indicators were detected by automatic biochemical analyzer, PCR, western blot, or ELISA. Statistics were analyzed using χ2-tests and t-tests. As the results, in cholelithiasis, MUC5AC highly expressed in the gallbladder shortened cholesterol supersaturation and promoted cholesterol crystallization via the inflammatory cytokine signaling pathway; MUC2 highly expressed in the small intestine prolonged cholesterol supersaturation and promoted cholesterol absorption via the inflammatory cytokine signaling pathway. YD inhibited mucin expression in the gallbladder and intestine in a concentration-dependent manner for cholelithiasis treatment by inhibiting the inflammatory cytokine signaling pathway, which was attributed to the active components, including chlorogenic acid, geniposide, and rhein.

Transient receptor potential channel 3 in human liver and gallbladder - An investigation in body donors.

Since the discovery of TRP proteins in 1969, during studies of the fruit fly Drosophila melanogaster, interest around them and the subfamily of TRPC channels has remained high. TRPC3 was able to be detected in a number of organs in rodents, such as rats and mice, and also in various human tissues. For the most part, these investigations were carried out using gene expression of TRPC3. Further work has already confirmed the relevance of TRPC3 in the context of neurodegenerative diseases, such as spinocerebellar ataxia, and carcinogenic entities, such as ovarian carcinoma. An association with TRPC3 has also been demonstrated for diseases that affect the liver. In order to confirm the expression of TRPC3 in the human liver, this study uses samples taken from eight (n = 8) fixated human body donors and analyzed with immunohistochemistry. In accordance with the macroscopic anatomy of the organs, six samples (n = 6) of liver tissue and three (n = 3) of gallbladder tissue were obtained. TRPC3 was clearly detected in all liver and gallbladder samples examined. Thus, it is not unlikely that TRPC3 plays a role in the extensive metabolic processes of the liver and could also serve as a target for pharmacological interventions in an imbalance of calcium homeostasis.

Liraglutide changes postprandial responses of gut hormones involved in the regulation of gallbladder motility.

AIM: Liraglutide treatment is associated with gallbladder-related disorders and has been shown to delay postprandial gallbladder refilling. The gut hormones cholecystokinin (CCK), fibroblast growth factor 19 (FGF19) and glucagon-like peptide 2 (GLP-2), are known to regulate gallbladder motility and may be implicated in gallbladder-related disorders associated with liraglutide treatment. MATERIALS AND METHODS: In a double-blind, 12-week trial, 52 participants [50% male, age 47.6 ± 10.0 years, body mass index 32.6 ± 3.4 kg/m2 (mean ± standard deviation)] with obesity were randomized 1:1 to once-daily subcutaneous liraglutide (escalated from 0.6 mg to 3.0 mg once-daily) or placebo. During liquid meal tests performed at baseline, after the first dose and following 12 weeks of treatment, we evaluated postprandial gallbladder dynamics and plasma responses of CCK, FGF19 and GLP-2. RESULTS: Liraglutide reduced postprandial FGF19 after the first dose [area under the curve (AUC)0-240 min 24.8 vs. 48.0 min × ng/ml, treatment ratio (TR) (95% confidence interval) 0.52 (0.39; 0.69)] and following 12 weeks of treatment [AUC0-240 min 33.7 vs. 48.5 ng/ml × min, TR 0.69 (0.52; 0.93)]. Liraglutide also reduced postprandial GLP-2 responses (AUC0-240 min 3650 vs. 4894 min × pmol/L, TR 0.75 (0.62; 0.90)] following the first dose as well as after 12 weeks [AUC0-240 min 3760 vs. 4882 min × pmol/L, TR 0.77 (0.60; 0.99)]. Liraglutide increased postprandial responses of CCK after the first dose [AUC0-240 min 762 vs. 670 min × pmol/L; TR 1.14 (0.97; 1.33)] and following 12 weeks of treatment [AUC0-240 min 873 vs. 628 min × pmol/L; TR 1.39 (1.12; 1.73)]. CONCLUSION: Compared with placebo, treatment with liraglutide decreased postprandial FGF19 and GLP-2 concentrations and increased postprandial CCK concentrations, which may explain the delayed postprandial gallbladder refilling observed in individuals with obesity treated with liraglutide.

Adeno-associated virus-based caveolin-1 delivery via different routes for the prevention of cholesterol gallstone formation.

BACKGROUND: Hepatic caveolin-1 (CAV1) is reduced in cholesterol gallstone disease (CGD). Mice with CAV1 deficiency were prone to develop CGD. However, it remains unknown whether restored hepatic CAV1 expression prevents the development of CGD. METHODS: C57BL/6 mice were injected with adeno-associated virus 2/8 (AAV2/8) vectors carrying the CAV1 gene (AAV2/8CAV1) via intravenous (i.v.) or intraperitoneal (i.p.) route and then subjected to a lithogenic diet (LD) for 8 weeks. Uninjected mice were used as controls. The functional consequences of rescuing CAV1 expression by either i.v. or i.p. AAV2/8CAV1 treatment for CGD prevention and its subsequent molecular mechanisms were examined. RESULTS: CAV1 expression was reduced in the liver and gallbladder of LD-fed CGD mice. We discovered that AAV2/8CAV1 i.p. delivery results in higher transduction efficiency in the gallbladder than tail vein administration. Although either i.v. or i.p. injection of AAV2/8CAV1 improved liver lipid metabolic abnormalities in CGD mice but did not affect LD feeding-induced bile cholesterol supersaturation. In comparison with i.v. administration route, i.p. administration of AAV2/8CAV1 obviously increased CAV1 protein levels in the gallbladder of LD-fed mice, and i.p. delivery of AAV2/8CAV1 partially improved gallbladder cholecystokinin receptor (CCKAR) responsiveness and impeded bile cholesterol nucleation via the activation of adenosine monophosphate-activated protein kinase (AMPK) signaling, which induced a reduction in gallbladder mucin-1 (MUC1) and MUC5ac expression and gallbladder cholesterol accumulation. CONCLUSION: CGD prevention by i.p. AAV2/8CAV1 injection in LD-fed mice was associated with the improvement of gallbladder stasis, which again supported the notion that supersaturated bile is required but not sufficient for the formation of cholesterol gallstones. Additionally, AAV treatment via the local i.p. injection offers particular advantages over the systemic i.v. route for much more effective gallbladder gene delivery, which will be an excellent tool for conducting preclinical functional studies on the maintenance of normal gallbladder function to prevent CGD.

Composition of chicken gallbladder bile.

1. The proximate composition and, amino acid, fatty acid and mineral profiles of gallbladder bile of 35 d old broiler chickens were determined.2. The dry matter (DM) content of the bile was determined to be 19.8 g/100 g. Fat, protein and ash contents in the bile were 24.9, 23.0 and 6.6 g/100 g DM, respectively.3. The content of total fatty acids (FA) in the bile was determined to be 17.68 g/100 g DM. Unsaturated FA dominated the profile in the bile, with an unsaturated: saturated FA ratio of 1.36. Oleic, linoleic, and arachidonic acids were the main unsaturated FA, whereas palmitic and stearic acids were the major saturated FA.4. A major finding was that the data established taurine as the primary amino acid in chicken bile and not glycine, as previously assumed. Taurine was the dominant amino acid, constituting 62% of bile protein.5. Among the major minerals, sodium (2.56 g/100 g DM) was in the greatest concentration. The concentrations of other major minerals were relatively low.6. The present work provided, for the first time, preliminary data on reference values for nutrients in the chicken gallbladder bile.

A Pro-Endocrine Pancreatic Islet Transcriptional Program Established During Development Is Retained in Human Gallbladder Epithelial Cells.

BACKGROUND & AIMS: Pancreatic islet ß-cells are factories for insulin production; however, ectopic expression of insulin also is well recognized. The gallbladder is a next-door neighbor to the developing pancreas. Here, we wanted to understand if gallbladders contain functional insulin-producing cells. METHODS: We compared developing and adult mouse as well as human gallbladder epithelial cells and islets using immunohistochemistry, flow cytometry, enzyme-linked immunosorbent assays, RNA sequencing, real-time polymerase chain reaction, chromatin immunoprecipitation, and functional studies. RESULTS: We show that the epithelial lining of developing, as well as adult, mouse and human gallbladders naturally contain interspersed cells that retain the capacity to actively transcribe, translate, package, and release insulin. We show that human gallbladders also contain functional insulin-secreting cells with the potential to naturally respond to glucose in vitro and in situ. Notably, in a non-obese diabetic (NOD) mouse model of type 1 diabetes, we observed that insulin-producing cells in the gallbladder are not targeted by autoimmune cells. Interestingly, in human gallbladders, insulin splice variants are absent, although insulin splice forms are observed in human islets. CONCLUSIONS: In summary, our biochemical, transcriptomic, and functional data in mouse and human gallbladder epithelial cells collectively show the evolutionary and developmental similarities between gallbladder and the pancreas that allow gallbladder epithelial cells to continue insulin production in adult life. Understanding the mechanisms regulating insulin transcription and translation in gallbladder epithelial cells would help guide future studies in type 1 diabetes therapy.

Risk of carcinogenesis in the biliary epithelium of children with congenital biliary dilatation through epigenetic and genetic regulation.

PURPOSES: Congenital biliary dilatation (CBD), defined as pancreaticobiliary maljunction (PBM) with biliary dilatation, is a high risk factor for biliary tract cancer (BTC). KRAS and p53 mutations reportedly affect this process, but the mechanisms are unclear, as is the likelihood of BTC later in life in children with CBD. We investigated potential carcinogenetic pathways in children with CBD compared with adults. METHODS: The subjects of this study were nine children with CBD and 13 adults with PBM (10 dilated, 3 non-dilated) without BTC who underwent extrahepatic bile duct resections, as well as four control patients who underwent pancreaticoduodenectomy for non-biliary cancer. We evaluated expressions of Ki-67, KRAS, p53, histone deacetylase (HDAC) and activation-induced cytidine deaminase (AID) in the biliary tract epithelium immunohistochemically. RESULTS: The Ki-67 labeling index (LI) and expressions of KRAS, p53, HDAC, and AID in the gallbladder epithelium were significantly higher or tended to be higher in both the children with CBD and the adults with PBM than in the controls. CONCLUSIONS: BTC may develop later in children with CBD and in adults with PBM, via HDAC and AID expression and through epigenetic and genetic regulation.

Advancing Estimation of Hepatobiliary Clearances in Physiologically Based Pharmacokinetic Models of Rosuvastatin Using Human Hepatic Concentrations.

PURPOSE: To estimate hepatobiliary clearances of rosuvastatin via simultaneously fitting to reported human positron emission tomography (PET) data in the liver and gallbladder. METHODS: A hepatobiliary model incorporating five intrinsic hepatobiliary clearances (active uptake clearance at the sinusoidal membrane, efflux clearance by passive diffusion through the sinusoidal membrane, influx clearance by passive diffusion through sinusoidal membrane, clearance of biliary excretion at the canalicular membrane, and intercompartment clearance from the intrahepatic bile duct to the gallbladder) and three compartments (liver, intrahepatic bile duct, and gallbladder) was developed to simultaneously fit rosuvastatin liver and gallbladder data from a representative subject reported by Billington et al. (1). Two liver blood supply input functions, arterial input function and dual input function (using peripheral venous as an alternative to portal vein), were assessed. Additionally, the predictive performance between the established model and four reported models trained with only systemic exposure data, was evaluated by comparing simulated liver and gallbladder profiles with observations. RESULTS: The established hepatobiliary model well captured the kinetic profiles of rosuvastatin in the liver and gallbladder during the PET scans. Application of dual input function led to a marked underestimation of liver concentrations at the initial stage after i.v. dosing which cannot be offset by altering model parameter values. The simulated hepatobiliary profiles from three of the reported models demonstrated substantial deviation from the observed data. CONCLUSIONS: The present study highlights the necessity of using hepatobiliary data to verify and improve the predictive performance of hepatic disposition of rosuvastatin.

Variation of enterohepatic circulation observed with 75SeHCAT images in the first three hours. Scintigraphic patterns and analysis of their association with the diagnosis of bile acid malabsorption.

OBJETIVE: To evaluate the enterohepatic circulation of 75-Selenium turoselecolic acid (75Se-SeHCAT) during the first 3 h and its correlation with the abdominal retention at the 7th day (AR7), as contribution to the clinical study of biliar acid malabsorption (BAM). MATERIALS AND METHODS: 38 patients with chronic diarrhea were retrospectively studied. Acquisition protocol included static abdominal images at 1st, 2nd and 3rd hour and the 7th day after oral administration of the radiopharmaceutical. Images of 1-3 h determined 5 patterns of enterohepatic circulation that, due to their location, were characterized as: 1) gallbladder 2-3 h, 2) gallbladder 3 h, 3) gallbladder-abdomen 2-3 h, 4) abdomen, 5) upper left abdomen. The association of these patterns with the AR7 (Fisher, STATA) were investigated. Patients were classified as Non BAM (AR7 > 15%), mild-BAM (AR7 15-10%), moderate-BAM (AR7 10-5%) or severe-BAM (AR7 < 5%). RESULTS: 19 patients had an AR7 diagnostic of BAM (7 mild-BAM, 5 moderate-BAM, 7 severe-BAM). The pattern "gallbladder at 2-3 h" was statistically associated with Non BAM (p 0,008), while "gallbladder-abdomen at 2-3 h" was correlated with having BAM (p 0,029). CONCLUSION: Variations detected at the abdominal level in images during the first 3 h were associated with changes in intestinal absorption and the incorporation of the radiopharmaceutical into the pool of bile acids, so visual interpretation of the images at 2nd and 3rd hour could be useful in the final assessment of the study.

miRNA-223 Suppresses Mouse Gallstone Formation by Targeting Key Transporters in Hepatobiliary Cholesterol Secretion Pathway.

miRNA-223 has been previously reported to play an essential role in hepatic cholesterol homeostasis. However, its role in regulation of biliary cholesterol secretion and gallstone formation remains unknown. Hence, mice with conventional knockout (KO), hepatocyte-specific knockout (ΔHepa) / knockdown (KD) or gain expression of miRNA-223 were included in the study and were subjected to lithogenic diet (LD) for various weeks. The gall bladders and liver tissues were harvested for cholesterol crystal imaging, gallstone mass measurement and molecular analysis. Levels of cholesterol, bile salt, phospholipids, and triglyceride were determined in serum, liver tissues, and bile by enzyme color reactive assays. A 3' UTR reporter gene assay was used to verify the direct target genes for miRNA-223. LD-induced gallstone formation was remarkably accelerated in miRNA-223 KO, ΔHepa, and KD mice with concurrent enhancement in total cholesterol levels in liver tissues and bile. Key biliary cholesterol transporters ABCG5 and ABCG8 were identified as direct targets of miRNA-223. Reversely, AAV-mediated hepatocyte-specific miRNA-223 overexpression prevented gallstone progression with reduced targets expression. Therefore, the present study demonstrates a novel role of miRNA-223 in the gallstone formation by targeting ABCG5 and ABCG8 and elevating miRNA-223 would be a potentially novel approach to overcome the sternness of cholesterol gallstone disease.

LncRNA EPIC1 promotes proliferation and inhibits apoptosis of gallbladder cancer cells by interacting with LET.

INTRODUCTION AND OBJECTIVES: Long non-coding RNA (lncRNA) EPIC1 (epigenetically-induced lncRNA1) is likely involved in human cancer by promoting cell cycle progression. Our study was carried out to investigate the involvement of EPIC1 in gallbladder cancer (GBC). METHODS: Expression levels of EPIC1 in two types of tissues (GBC and paracancerous) and plasma were measured by performing qPCR. GBC-SD and SGC-996 cells were transfected with low expression in tumor (LET) and EPIC1 expression vectors. RESULTS: The present study found that EPIC1 was upregulated in tumor tissues than in paracancerous tissues of GBC patients, and plasma levels of EPIC1 were significantly correlated with levels of EPIC1 in tumor tissues. LncRNA LET was downregulated in tumor tissues than in paracancerous tissues and was inversely correlated with EPIC1 in both tumor tissues and paracancerous tissues. Overexpression of EPIC1 led to downregulated LET, and LET overexpression also mediated the downregulation of EPIC1. EPIC1 led to accelerated GBC cell proliferation and inhibited apoptosis. Overexpression of LET played opposites roles. In addition, LET overexpression attenuated the effects of EPIC1 overexpression on cancer cell proliferation and apoptosis. CONCLUSIONS: LncRNA EPIC1 promoted proliferation and inhibited apoptosis of GBC cells by interacting with LET.

Free fatty acids and triglyceride change in the gallbladder bile of gallstone patients with pancreaticobiliary reflux.

BACKGROUND: Pancreaticobiliary reflux (PBR) causes chronic inflammation of the gallbladder mucosa and changes in the bile components, which are known to promote gallstone formation. This study aimed to investigate the bile biochemistry changes in gallstone patients with PBR and provide new clues for research on the involvement of PBR in gallstone formation. METHODS: Patients undergoing surgery for gallstones between December 2020 and May 2021 were eligible for inclusion. The bile biochemistry (including amylase, lipase, triglyceride, cholesterol, free fatty acids [FFAs], alanine aminotransferase [ALT], aspartate aminotransferase [AST], alkaline phosphatase [ALP], and γ-glutamyl transferase [γ-GT]) of the included gallstone patients was analysed to determine correlations with PBR. RESULTS: In this study, 144 gallstone patients who underwent surgery were enrolled. Overall, 15.97 % of the patients had an increased bile amylase level, which was associated with older age and significantly higher bile levels of ALP, lipase, triglyceride, and FFAs. Positive correlations were observed between amylase and lipase, triglyceride, FFAs levels in the gallbladder bile. However, the bile levels of triglyceride, FFAs, and lipase were positively correlated with each other only in the PBR group and showed no significant correlation in the control (N) group. In addition, elevated bile FFAs levels were found to be an independent risk factor for gallbladder wall thickening. CONCLUSIONS: In conclusion, PBR-induced increase in FFAs and triglyceride in the gallbladder bile is a cause of gallstone formation, and an increase in bile ALP suggests the presence of cholestasis in PBR.

A Molecular-Splicing Strategy for Constructing a Near-Infrared Fluorescent Probe for UDP-Glucuronosyltransferase 1A1.

UDP-glucuronosyltransferase 1A1 (UGT1A1) is a vital metabolic enzyme responsible for the clearance of endogenous substances and drugs. Hitherto, the development of fluorescent probes for UGTs was severely restricted due to the poor isoform selectivity and on-off or blue-shifted fluorescence response. Herein, we established a novel "molecular-splicing" strategy to construct a highly selective near-infrared (NIR) fluorescent probe, HHC, for UGT1A1, which exhibited a NIR signal at 720 nm after UGT1A1 metabolism. HHC was then successfully used for the real-time imaging of endogenous UGT1A1 in living cells and animals and to monitor the bile excretion function. In summary, an isoform-specific NIR fluorescent probe has been developed for monitoring UGT1A1 activity in living systems, high-throughput screening of novel UGT1A1 inhibitors and visual evaluation of bile excretion function.

Liver X receptor ß regulates bile volume and the expression of aquaporins and cystic fibrosis transmembrane conductance regulator in the gallbladder.

The gallbladder is considered an important organ in maintaining digestive and metabolic homeostasis. Given that therapeutic options for gallbladder diseases are often limited to cholecystectomy, understanding gallbladder pathophysiology is essential in developing novel therapeutic strategies. Since liver X receptor ß (LXRß), an oxysterol-activated transcription factor, is strongly expressed in gallbladder cholangiocytes, the aim was to investigate LXRß physiological function in the gallbladder. Thus, we studied the gallbladders of WT and LXRß-/- male mice using immunohistochemistry, electron microscopy, qRT-PCR, bile duct cannulation, bile and blood biochemistry, and duodenal pH measurements. LXRß-/- mice presented a large gallbladder bile volume with high duodenal mRNA levels of the vasoactive intestinal polypeptide (VIP), a strong mediator of gallbladder relaxation. LXRß-/- gallbladders showed low mRNA and protein expression of Aquaporin-1, Aquaporin-8, and cystic fibrosis transmembrane conductance regulator (CFTR). A cystic fibrosis-resembling phenotype was evident in the liver showing high serum cholestatic markers and the presence of reactive cholangiocytes. For LXRß being a transcription factor, we identified eight putative binding sites of LXR on the promoter and enhancer of the Cftr gene, suggesting Cftr as a novel LXRß regulated gene. In conclusion, LXRß was recognized as a regulator of gallbladder bile volume through multiple mechanisms involving CFTR and aquaporins.NEW & NOTEWORTHY This report reveals a novel and specific role of the nuclear receptor liver X receptor ß (LXRß) in controlling biliary tree pathophysiology. LXRß-/- mice have high gallbladder bile volume and are affected by a cholangiopathy that resembles cystic fibrosis. We found LXRß to regulate the expression of both aquaporins water channels and the cystic fibrosis transmembrane conductance regulator. This opens a new field in biliary tree pathophysiology, enlightening a possible transcription factor controlling CFTR expression.

Digested soybean protein and taurine influence bile acid level, lipase activity, lipid digestibility, and growth performance of pompano (Trachinotus blochii).

This study aimed to examine the effects of dietary digested soybean protein (DSP) and taurine on bile acid (BA) level, lipase activity, lipid apparent digestibility coefficient (ADC), and growth performance of pompano (Trachinotus blochii). Five diets were formulated with fish meal (FM), defatted soybean meal (SBM), and the DSP as main dietary protein sources. The diets were denoted as follows: FMD (FM-based diet), SBMD (SBM-based diet), SBM+TD (SBM-based diet plus taurine), DSPD (DSP-based diet), and DSP+TD (DSP-based diet plus taurine). Fingerling pompano with an initial body weight (BW) of 21.4 g were stocked in 500-L tanks, with triplicate tanks per dietary treatment. For 8 weeks, the fish were hand-fed the experimental diets to apparent satiation twice daily. The results showed that the DSPD and DSP+TD groups had significantly higher final BW, weight gain, and specific growth rate, but lower feed conversion ratio, than the SBMD and SBM+TD groups, respectively (P < 0.05). There were no significant differences in growth and feed performances between fish fed DSP+TD and FMD. The gallbladder and anterior intestinal BA levels, anterior intestinal lipase activity, and lipid and protein ADCs were markedly increased in fish fed DSPD and DSP+TD compared to those fed SBMD (P < 0.05), and no significant differences were detected between the DSP+TD and FMD groups. The findings of the present study suggested that dietary DSP inclusion with taurine supplementation might effectively improve lipid digestion and this contributed to growth enhancement in pompano fed a soybean protein-based diet.

TUBB3 Promotes Growth and Invasion of Gallbladder Cancer Cells by Akt/mTOR Signal Pathway.

Aberrant expression of ß-tubulin-III (TUBB3) is known that related to aggressive tumor features and poor clinical outcomes. However, there is limited research about TUBB3 expression and its role in the outcomes and the progression of gallbladder cancer. We have measured TUBB3 level in gallbladder cancer samples and cell lines from 2012 to 2016, and tested the effects of TUBB3 in cancer cell growth, apoptosis and cell cycle arrest by using appropriate methods. The results revealed that TUBB3 was significantly over-expressed in gallbladder cancer samples and cell lines, and high TUBB3 level contributed to shorter overall survival in patients. The knockdown of TUBB3 with sh-TUBB3 inhibited the proliferation, migration and invasion of cancer cells. Meanwhile, it promotes apoptosis and changes the cell cycle distribution. Suppression of TUBB3 expression could increase p21 and cyclin B1 expression, and decrease cyclin D1. Xenograft mouse model also showed that low expression of TUBB3 reduced the growth of established gallbladder cancer xenograft in vivo. Furthermore, TUBB3 knockdown significantly decreased phosphorylation of Akt and mTOR in vitro and in vivo. TUBB3 can induce the development of gallbladder cancer by Akt/mTOR signal pathway and we point out a potential therapeutic target for gallbladder cancer treatment.