Effects Of UDCA Research Articles

A novel model to study mechanisms of cholestasis in human cholangiocytes reveals a role for the SIPR2 pathway.

Ductular reactivity is central to the pathophysiology of cholangiopathies. Mechanisms underlying the reactive phenotype activation by exogenous inflammatory mediators and bile acids are poorly understood. Using human extrahepatic cholangiocyte organoids (ECOs) we developed an injury model emulating the cholestatic microenvironment with exposure to inflammatory mediators and various pathogenic bile acids. Moreover, we explored roles for the bile acid activated Sphingosine-1-phosphate receptor 2 (S1PR2) and potential beneficial effects of therapeutic bile acids UDCA and norUDCA. Synergistic exposure to bile acids (taurocholic acid, glycocholic acid, glycochenodeoxycholic acid) and TNF-α for 24 hours induced a reactive state as measured by ECO diameter, proliferation, lactate dehydrogenase activity and reactive phenotype markers. While NorUDCA and UDCA treatments given 8 hours after injury induction both suppressed reactive phenotype activation and most injury parameters, proliferation was improved by NorUDCA only. Extrahepatic cholangiocyte organoid stimulation with S1PR2 agonist sphingosine-1-phosphate reproduced the cholangiocyte reactive state and upregulated S1PR2 downstream mediators; these effects were suppressed by S1PR2 antagonist JET-013 (JET), downstream mediator extracellular signal-regulated kinase 1/2 inhibitor, and by norUDCA or UDCA treatments. JET also partially suppressed reactive phenotype after bile acid injury. We developed a novel model to study the reactive cholangiocyte state in response to pathological stimuli in cholestasis and demonstrated a contributory role of S1PR2 signaling in both injury and NorUDCA/UDCA treatments. This model is a valuable tool to further explore the pathophysiology of human cholangiopathies.

Comparative Analysis of Urso- and Tauroursodeoxycholic Acid Neuroprotective Effects on Retinal Degeneration Models.

Ursodeoxycholic (UDCA) and tauroursodeoxycholic (TUDCA) acids have shown neuroprotective properties in neurodegenerative diseases, but differential effects of the two bile acids have been poorly explored. The aim of this study was to evaluate the neuroprotective effects of UDCA versus TUDCA in a neuroretinal degeneration model and to compare transcriptionally regulated pathways. The WERI-Rb-1 human cone-like cell line and retinal explants were exposed to albumin and TUDCA or UDCA. Viability, cell death, and microglial activation were quantified. Transcriptionally regulated pathways were analyzed after RNA sequencing using the edgeR bioconductor package. Pre-treatment of cone-like cells with UDCA or TUDCA significantly protected cells from albumin toxicity. On retinal explants, either bile acid reduced apoptosis, necroptosis, and microglia activation at 6 h. TUDCA induced the regulation of 463 genes, whilst 31 genes were regulated by UDCA. Only nineteen common genes were regulated by both bile acids, mainly involved in iron control, cell death, oxidative stress, and cell metabolism. As compared to UDCA, TUDCA up-regulated genes involved in endoplasmic reticulum stress pathways and down-regulated genes involved in axonal and neuronal development. Either bile acid protected against albumin-induced cell loss. However, TUDCA regulated substantially more neuroprotective genes than UDCA.

1197. Inhibitory Effect of Ursodeoxycholic Acid on Clostridioides difficile Growth

BackgroundUrsodeoxycholic acid (UDCA), a secondary bile acid, inhibits germination and growth of Clostridioides difficile in vitro, but the results from in vivo experiments have been conflicting. We evaluated the effects of UDCA on C. difficile in vitro and in a wax moth, Galleria mellonella model.MethodsThe in vitro growth and germination effects of UDCA on C. difficile were assessed with increased concentration of UDCA (0.001, 0.01, 0.05, and 0.1%). To assess treatment effects of UDCA, C. difficile spores (approximately 1x10^6-8 colony forming units (CFU)) were force fed to G. mellonella larvae treated with UDCA (50 mg/kg/day) 24 hours prior to C. difficile inoculation. Forty G. mellonella larvae were used for each experiment, which was repeated with two distinct strains (R20291 and CD196). Larvae were housed at 37°C and monitored for the next five days for mortality.ResultsIn vitro experiment demonstrated inhibition of C. difficile growth at 0.1% concentration (P < 0.001 vs control). Larvae treated with UDCA had a numerically higher survival rate (60% / 24/40) compared to controls (40% / 16/40) but the results were not statistically significant (p=0.14). Identical rates of survival were observed in the control arms for both strains (40%) and similar in the treatment arms (R20291: 70%; CD 196: 50%).ConclusionOverall, UDCA shows inhibitory effect of growth and germination of C. difficile in vitro. However, in our G. mellonella model, a single dose of UDCA given prior to infection did not prevent CDI. Further dose dependent, and multiday studies investigating the role of UDCA in CDI is needed to better understand this in vitro / in vivo paradox.Disclosures Kevin W. Garey, PharMD, MS, FASHP, Merck & Co. (Grant/Research Support, Scientific Research Study Investigator)

Abstract LB-298: Gut microbiota changes in response to treatment with ursodeoxycholic acid

Abstract Compelling evidence suggests that the gut flora influences colorectal cancer risk through direct effects on colonic bile acid composition. Bile acids are widely implicated in the etiology of colorectal cancer and the strongest evidence is for the secondary bile acid deoxycholic acid. In a study of patients with prior colorectal adenomas who were randomized to ursodeoxycholic acid (n = 188 males, 64 females), a bile acid based intervention aimed at modulating bile acid composition, or placebo (n = 162 males, 89 females), we determined effects of the intervention on the gut microbiome through 16S rRNA sequencing and bile acid composition using mass spectrometry. We observe a consistent shift in microbial community phylogenetic composition for males (t = 5.83, p = 3.6e-8) and females (t = 3.14, p = 0.003) treated with UDCA. No effect was observed in the placebo group for either males (t = -0.08, p = 0.93) or females (t = -0.09, p = 0.92). This suggests that UDCA treatment, but not placebo treatment, is having an effect on the gut microbial communities of study participants. Interestingly, the microbiomes of the UDCA group do not change more than those of the placebo group: rather the magnitude of change is similar in the two groups, but UDCA treatment seems to drive specific microbiome changes. We also observe significant correlations between the gut microbiome composition and bile acid composition (r = 0.31, p&amp;lt;0.001). Specifically we find that (prior to treatment) bile acids including CA, CDCA, and UDCA are negatively correlated with diversity (richness) and to a lesser extent the abundance of Bacteroidetes (phylum) in the gut. These results are consistent with our previously reported observation that UDCA appears to have a greater effect in men for the prevention of colorectal adenomatous polyps, with risk-increasing effects for women. To our knowledge, this is the first study to correlate fecal bile acid levels with fecal microbial composition in humans or to assess the effect of the therapeutic bile acid UDCA on gut microbial composition. This study supports our observation that the efficacy of UDCA for the prevention of colorectal adenoma may be sex-dependent and suggests that the sex-specific effect may reflect differential effects of UDCA on the gut microbial community and the relationship between sex, the gut microbiome, and risk of colorectal adenomatous polyps. Citation Format: J Gregory Caporaso, Talima Pearson, Monia Yellowhair, Jessica Martinez, Peter Lance. Gut microbiota changes in response to treatment with ursodeoxycholic acid. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr LB-298.

Ursodeoxycholic Acid but Not Tauroursodeoxycholic Acid Inhibits Proliferation and Differentiation of Human Subcutaneous Adipocytes

Stress of endoplasmic reticulum (ERS) is one of the molecular triggers of adipocyte dysfunction and chronic low inflammation accompanying obesity. ERS can be alleviated by chemical chaperones from the family of bile acids (BAs). Thus, two BAs currently used to treat cholestasis, ursodeoxycholic and tauroursodeoxycholic acid (UDCA and TUDCA), could potentially lessen adverse metabolic effects of obesity. Nevertheless, BAs effects on human adipose cells are mostly unknown. They could regulate gene expression through pathways different from their chaperone function, namely through activation of farnesoid X receptor (FXR) and TGR5, G-coupled receptor. Therefore, this study aimed to analyze effects of UDCA and TUDCA on human preadipocytes and differentiated adipocytes derived from paired samples of two distinct subcutaneous adipose tissue depots, abdominal and gluteal. While TUDCA did not alter proliferation of cells from either depot, UDCA exerted strong anti-proliferative effect. In differentiated adipocytes, acute exposition to neither TUDCA nor UDCA was able to reduce effect of ERS stressor tunicamycin. However, exposure of cells to UDCA during whole differentiation process decreased expression of ERS markers. At the same time however, UDCA profoundly inhibited adipogenic conversion of cells. UDCA abolished expression of PPARγ and lipogenic enzymes already in the early phases of adipogenesis. This anti-adipogenic effect of UDCA was not dependent on FXR or TGR5 activation, but could be related to ability of UDCA to sustain the activation of ERK1/2 previously linked with PPARγ inactivation. Finally, neither BAs did lower expression of chemokines inducible by TLR4 pathway, when UDCA enhanced their expression in gluteal adipocytes. Therefore while TUDCA has neutral effect on human preadipocytes and adipocytes, the therapeutic use of UDCA different from treating cholestatic diseases should be considered with caution because UDCA alters functions of human adipose cells.

Liver protective effect of ursodeoxycholic acid includes regulation of ADAM17 activity

BackgroundUrsodeoxycholic acid (UDCA) is used to treat primary biliary cirrhosis, intrahepatic cholestasis, and other cholestatic conditions. Although much has been learned about the molecular basis of the disease pathophysiology, our understanding of the effects of UDCA remains unclear. Possibly underlying its cytoprotective, anti-apoptotic, anti-oxidative effects, UDCA was reported to regulate the expression of TNFα and other inflammatory cytokines. However, it is not known if this effect involves also modulation of ADAM family of metalloproteinases, which are responsible for release of ectodomains of inflammatory cytokines from the cell surface. We hypothesized that UDCA modulates ADAM17 activity, resulting in amelioration of cholestasis in a murine model of bile duct ligation (BDL).MethodsThe effect of UDCA on ADAM17 activity was studied using the human liver hepatocellular carcinoma cell line HepG2. Untransfected cells or cells ectopically expressing human ADAM17 were cultured with or without UDCA and further activated using phorbol-12-myristate-13-acetate (PMA). The expression and release of ADAM17 substrates, TNFα, TGFα, and c-Met receptor (or its soluble form, sMet) were evaluated using ELISA and quantitative real-time (qRT) PCR. Immunoblotting analyses were conducted to evaluate expression and activation of ADAM17 as well as the level of ERK1/2 phosphorylation after UDCA treatment. The regulation of tissue inhibitor of metalloproteinases-1 (TIMP-1) by UDCA was studied using zymography and qRT-PCR. A mouse model of acute cholestasis was induced by common BDL technique, during which mice received daily orogastric gavage with either UDCA or vehicle only. Liver injury was quantified using alkaline phosphatase (ALP), relative liver weight, and confirmed by histological analysis. ADAM17 substrates in sera were assessed using a bead multiplex assay.ResultsUDCA decreases amount of shed TNFα, TGFα, and sMet in cell culture media and the phosphorylation of ERK1/2. These effects are mediated by the reduction of ADAM17 activity in PMA stimulated cells although the expression ADAM17 is not affected. UDCA reduced the level of the mature form of ADAM17. Moreover, UDCA regulates the expression of TIMP-1 and gelatinases activity in PMA stimulated cells. A BDL-induced acute cholangitis model was characterized by increased relative liver weight, serum levels of ALP, sMet, and loss of intracellular glycogen. UDCA administration significantly decreased ALP and sMet levels, and reduced relative liver weight. Furthermore, hepatocytes of UDCA-treated animals retained their metabolic activity as evidenced by the amount of glycogen storage.ConclusionsThe beneficial effect of UDCA appears to be mediated in part by the inhibition of ADAM17 activation and, thus, the release of TNFα, a strong pro-inflammatory factor. The release of other ADAM17 substrates, TGFα and sMet, are also regulated this way, pointing to a general impact on the release of ADAM17 substrates, which are pivotal for liver regeneration and function. In parallel, UDCA upregulates TIMP-1 that in turn inhibits matrix metalloproteinases, which destroy the hepatic ECM in diseased liver. This control of extracellular matrix turnover represents an additional beneficial path of UDCA treatment.

Differential effects of norUDCA and UDCA in obstructive cholestasis in mice

Background & AimsThe quest for effective drugs to treat cholangiopathies led to the development of norUDCA previously shown to have potent choleretic effects and to heal cholangiopathy in Abcb4 knockout (Abcb4−/−) mice. Its mother compound UDCA had detrimental effects in common bile duct ligated (CBDL) mice, presumably related to its choleretic effects. norUDCA choleretic effects may therefore raise safety concerns when used in cholangiopathies with biliary obstruction. We therefore aimed at comparing the effects of UDCA and norUDCA in clear-cut obstructive cholestasis.Methods0.5% UDCA- or norUDCA-fed wild type and Abcb4−/− mice were subjected to CBDL or selective bile duct ligation (SBDL) and compared to controls with regard to liver injury. Bile flow, bile composition, and biliary manometry were compared in UDCA-fed, norUDCA-fed and control mice. Toxicity of UDCA and norUDCA was compared in vitro.ResultsCompared to UDCA, liver injury in CBDL mice was significantly lower in almost all norUDCA groups. In SBDL mice, only UDCA induced bile infarcts in the ligated lobes, whereas norUDCA even ameliorated liver injury. In vitro, UDCA induced cellular ATP depletion and was significantly more toxic than norUDCA in HepG2 cells, mouse bile duct epithelial cells, and primary human hepatocytes.ConclusionsCompared to norUDCA, UDCA is significantly more toxic in CBDL mice. norUDCA, in contrast to UDCA, significantly ameliorates liver injury in SBDL mice. Our findings uncover profound differences in metabolism and therapeutic mechanisms of both bile acids with important clinical consequences.

Unusual binding of ursodeoxycholic acid to ileal bile acid binding protein: role in activation of FXRα

Ursodeoxycholic acid (UDCA, ursodiol) is used to prevent damage to the liver in patients with primary biliary cirrhosis. The drug also prevents the progression of colorectal cancer and the recurrence of high-grade colonic dysplasia. However, the molecular mechanism by which UDCA elicits its beneficial effects is not entirely understood. The aim of this study was to determine whether ileal bile acid binding protein (IBABP) has a role in mediating the effects of UDCA. We find that UDCA binds to a single site on IBABP and increases the affinity for major human bile acids at a second binding site. As UDCA occupies one of the bile acid binding sites on IBABP, it reduces the cooperative binding that is often observed for the major human bile acids. Furthermore, IBABP is necessary for the full activation of farnesoid X receptor α (FXRα) by bile acids, including UDCA. These observations suggest that IBABP may have a role in mediating some of the intestinal effects of UDCA.

S1903 Beneficial Effects of UDCA and Ncx-1000 Alone or in Combination with Vitamin E in a Nonalcoholic Steatohepatitis Rat Model

S1903 Beneficial Effects of UDCA and Ncx-1000 Alone or in Combination with Vitamin E in a Nonalcoholic Steatohepatitis Rat Model

Combination of ursodeoxycholic acid and glucocorticoids upregulates the AE2 alternate promoter in human liver cells

Primary biliary cirrhosis (PBC) is a cholestatic disease associated with autoimmune phenomena and alterations in both biliary bicarbonate excretion and expression of the bicarbonate carrier AE2. The bile acid ursodeoxycholic acid (UCDA) is currently used in treatment of cholestatic liver diseases and is the treatment of choice in PBC; however, a subset of PBC patients respond poorly to UDCA monotherapy. In these patients, a combination of UDCA and glucocorticoid therapy appears to be beneficial. To address the mechanism of this benefit, we analyzed the effects of UDCA and dexamethasone on AE2 gene expression in human liver cells from hepatocyte and cholangiocyte lineages. The combination of UDCA and dexamethasone, but not UDCA or dexamethasone alone, increased the expression of liver-enriched alternative mRNA isoforms AE2b1 and AE2b2 and enhanced AE2 activity. Similar effects were obtained after replacing UDCA with UDCA conjugates. In in vitro and in vivo reporter assays, we found that a UDCA/dexamethasone combination upregulated human AE2 alternate overlapping promoter sequences from which AE2b1 and AE2b2 are expressed. In chromatin immunoprecipitation assays, we demonstrated that combination UCDA/dexamethasone treatment induced p300-related interactions between HNF1 and glucocorticoid receptor on the AE2 alternate promoter. Our data provide a potential molecular explanation for the beneficial effects of the combination of UDCA and glucocorticoids in PBC patients with inadequate response to UDCA monotherapy.

Effects of UDCA on the foetus-maternal circulation of bilirubin in cholestasis of pregnancy

Background and aim. Prematurity is frequent in intrahepatic cholestasis of pregnancy (ICP) and represent a risk factor for bilirubin neurotoxicity in the newborn. Aim of our study was to investigate the foetus-maternal circulation of bilirubin which is still undefined.

17β‐estradiol prevents cytotoxicity from hydrophobic bile acids in HepG2 and WRL‐68 cell cultures

Epidemiological and clinical studies suggest the possibility that estrogens might have a cytoprotective effect on the liver. The aim of the present study was to test the hypothesis that 17beta-estradiol (E2) prevents hepatocellular damage induced by deoxycholic acid (DCA), a hydrophobic bile acid. HepG2 cells were exposed for 24 h to DCA (350 micromol/L). Cell viability, aspartate aminotransferase and lactate dehydrogenase activity and apoptosis were measured as indices of cell toxicity. The effect of DCA was compared to that observed using either a hydrophilic bile acid, ursodeoxycholic acid (UDCA; 100 micromol/L), or E2 at different concentrations (1 nmol/L, 10 nmol/L, 50 nmol/L and 50 micromol/L) or mixtures of E2/DCA or UDCA/DCA. The same experiments were performed using WRL-68 cells that, at variance with HepG2, express a higher level of nuclear estrogen receptor. High concentrations of E2 and UDCA prevented DCA-induced decrease in cell viability, increase in enzyme activity and apoptosis evaluated both by 4',6-diamidino-2-phenylindole dihydrochloride (DAPI) and TdT-mediated dUTP nick-end labeling (TUNEL) assays. In addition, DCA-related apoptosis, assessed by caspase activity, was also prevented by E2 (P < 0.01) in physiological (1-10 nmol/L) doses. The cytoprotective effects of E2 and UDCA was also observed in the WRL-68 cell line. 17Beta-Estradiol prevents DCA-induced cell damage in HepG2 and WRL-68 cell lines to an extent comparable to UDCA. The hypothesis that the protective effect of E2 may be mediated by a mechanism that is nuclear estrogen receptor independent, deserves further verification.

Ursodeoxycholic acid differentially affects three types of sphingomyelinase in human colon cancer Caco 2 cells

We investigated the effects of UDCA on sphingomyelinase (SMase) in Caco 2 cells cultured in monolayer and polarized conditions. Alkaline SMase activity was high in polarized cells whereas, acid and neutral SMase activities were high in monolayer cells. In polarized cells, UDCA increased alkaline SMase expression and caspase 3 activity but had no effect on acid and neutral SMases. In monolayer cells, UDCA reduced both acid and neutral SMase activities, inhibited cell proliferation, but had little effect on alkaline SMase and caspase 3 activities. In conclusion, UDCA differentially affects SMase activity, cell proliferation, and apoptosis in colonic cells depending on the cell conditions.

Ursodeoxycholic acid in cholestatic liver disease: Mechanisms of action and therapeutic use revisited

Ursodeoxycholic acid (UCDA) is increasingly used for the treatment of cholestatic liver diseases. Experimental evidence suggests three major mechanisms of action: (1) protection of cholangiocytes against cytotoxicity of hydrophobic bile acids, resulting from modulation of the composition of mixed phospholipid-rich micelles, reduction of bile acid cytotoxicity of bile and, possibly, decrease of the concentration of hydrophobic bile acids in the cholangiocytes; (2) stimulation of hepatobiliary secretion, putatively via Ca 2+- and protein kinase C-α–dependent mechanisms and/or activation of p38 MAPK and extracellular signal-regulated kinases (Erk) resulting in insertion of transporter molecules ( e.g., bile salt export pump, BSEP, and conjugate export pump, MRP2) into the canalicular membrane of the hepatocyte and, possibly, activation of inserted carriers; (3) protection of hepatocytes against bile acid–induced apoptosis, involving inhibition of mitochondrial membrane permeability transition (MMPT), and possibly, stimulation of a survival pathway. In primary biliary cirrhosis, UDCA (13-15 mg/kg/d) improves serum liver chemistries, may delay disease progression to severe fibrosis or cirrhosis, and may prolong transplant-free survival. In primary sclerosing cholangitis, UDCA (13-20 mg/kg/d) improves serum liver chemistries and surrogate markers of prognosis, but effects on disease progression must be further evaluated. Anticholestatic effects of UDCA have also been reported in intrahepatic cholestasis of pregnancy, liver disease of cystic fibrosis, progressive familial intrahepatic cholestasis, and chronic graft-versus-host disease. Future efforts will focus on definition of additional clinical uses of UDCA, on optimized dosage regimens, as well as on further elucidation of mechanisms of action of UDCA at the molecular level. (H EPATOLOGY 2002;36:525-531.)

Prognostic factors and long-term effects of ursodeoxycholic acid on liver biochemical parameters in patients with primary biliary cirrhosis

Background/Aims: Serum bilirubin is a prognostic factor in untreated primary biliary cirrhosis (PBC), but this has been less extensively documented for patients treated with UDCA. The aims of this study were to define the effects of UDCA on serum liver tests and to assess prognostic factors in patients on prolonged UDCA treatment. Methods: Analysis of laboratory parameters obtained before and during treatment with UDCA of 203 PBC patients who were followed for a mean of 48 months. Univariate and multivariate analyses were performed to assess the prognostic value of pre-entry and follow-up variables with respect to treatment failure and survival. Results: Actuarial 5-year incidences of treatment failure and transplantion-free survival were 27 and 79%, respectively. According to the univariate analysis the following variables were significantly associated with prognosis: pre-entry presence of cirrhosis and pretreatment levels of serum bilirubin and albumin, bilirubin levels during follow-up, the occurrence of biochemical remission and normalisation of serum bilirubin. Multivariate analysis revealed that bilirubin during follow-up was the best predictor. Alkaline phophatase, aspartate aminotransferase and IgM decreased significantly during the first 6 months of treatment and subsequently remained at this lower level. Serum bilirubin showed the same initial pattern, but a significant increase was observed after 4 years of treatment. Conclusions: Serum bilirubin in both UDCA-treated and untreated patients is the most powerful predictor of prognosis for PBC. The partial therapeutic efficacy of UDCA is illustrated by the finding that serum bilirubin, in contrast to alkaline phosphatase and the transaminases, appears to increase after 4 years of treatment.

A Short-Term Study of the Effects of UDCA on Gingival Inflammation in the Beagle Dog

A Short-Term Study of the Effects of UDCA on Gingival Inflammation in the Beagle Dog