Biliary Excretion Research Articles

Type II choledochal cyst of the cystic duct in a 3 Month old

Type II choledochal cysts are rare, representing approximately 2% of cases [1-3]. Even fewer cases of type II cysts involving the cystic duct have been reported. Excision is necessary to prevent future ascending cholangitis, liver fibrosis, and malignancy [1-3, 5]. We present a case of a 3 month old male born premature who presented with persistent conjugated hyperbilirubinemia. Imaging workup demonstrated a cystic structure at the neck of the cystic duct, measuring 0.9 cm × 1.6 cm x 0.9 cm. Delayed biliary excretion was noted on HIDA. Decision was made to take the patient to the operating room for a cholecystectomy and intraoperative cholangiogram to delineate the anatomy. Intraoperatively, the patient was found to have a small cystic structure arising from the cystic duct. A cholecystectomy was performed and the patient recovered well. Choledochal cysts of the cystic duct are considered type II cysts based on the original Todani Classification. Due to their location, cholecystectomy is required during excision [1-3,5]. Wide-based cysts involving the common bile duct additionally require hepaticojejunostomy [1-3,5]. • Type II choledochal cysts represent 2% of cases. Even fewer involve the cystic duct. • Choledochal cysts of the cystic duct are type II cysts based on Todani classification. • Excision is indicated to prevent cholangitis, liver fibrosis, and malignancy. • Surgical management involves cholecystectomy with or without hepaticojejunostomy.

Inhibition of canalicular and sinusoidal taurocholate efflux by cholestatic drugs in human hepatoma HepaRG cells.

HepaRG cells are highly-differentiated human hepatoma cells, which are increasingly recognized as a convenient cellular model for in vitro evaluation of hepatic metabolism, transport, and/or toxicity of drugs. The present study was designed to evaluate whether HepaRG cells can also be useful for studying drug-mediated inhibition of canalicular and/or sinusoidal hepatic efflux of bile acids, which constitutes a major mechanism of drug-induced liver toxicity. For this purpose, HepaRG cells, initially loaded with the bile acid taurocholate (TC), were reincubated in TC-free transport assay medium, in the presence or absence of calcium or drugs, before analysis of TC retention. This method allowed us to objectivize and quantitatively measure biliary and sinusoidal efflux of TC from HepaRG cells, through distinguishing cellular and canalicular compartments. In particular, time-course analysis of the TC-free reincubation period of HepaRG cells, that is, the efflux period, indicated that a 20min-efflux period allowed reaching biliary and sinusoidal excretion indexes for TC around 80% and 60%, respectively. Addition of the prototypical cholestatic drugs bosentan, cyclosporin A, glibenclamide, or troglitazone during the TC-free efflux phase period was demonstrated to markedly inhibit canalicular and sinusoidal secretion of TC, whereas, by contrast, incubation with the noncholestatic compounds salicylic acid or flumazenil was without effect. Such data therefore support the use of human HepaRG cells for in vitro predicting drug-induced liver toxicity (DILI) due to the inhibition of hepatic bile acid secretion, using a biphasic TC loading/efflux assay.

In Vivo Fate of Cowpea Mosaic Virus In Situ Vaccine: Biodistribution and Clearance.

Cowpea mosaic virus (CPMV) is a nucleoprotein nanoparticle that functions as a highly potent immunomodulator when administered intratumorally and is used as an in situ vaccine. CPMV in situ vaccination remodels the tumor microenvironment and primes a highly potent, systemic, and durable antitumor immune response against the treated and untreated, distant metastatic sites (abscopal effect). Potent efficacy was demonstrated in multiple tumor mouse models and, most importantly, in canine cancer patients with spontaneous tumors. Data indicate that presence of anti-CPMV antibodies are not neutralizing and that in fact opsonization leads to enhanced efficacy. Plant viruses are part of the food chain, but to date, there is no information on human exposure to CPMV. Therefore, patient sera were tested for the presence of immunoglobulins against CPMV, and indeed, >50% of deidentified patient samples tested positive for CPMV antibodies. To get a broader sense of plant virus exposure and immunogenicity in humans, we also tested sera for antibodies against tobacco mosaic virus (>90% patients tested positive), potato virus X (<20% patients tested positive), and cowpea chlorotic mottle virus (no antibodies were detected). Further, patient sera were analyzed for the presence of antibodies against the coliphage Qβ, a platform technology currently undergoing clinical trials for in situ vaccination; we found that 60% of patients present with anti-Qβ antibodies. Thus, data indicate human exposure to CPMV and other plant viruses and phages. Next, we thought to address agronomical safety; i.e., we examined the fate of CPMV after intratumoral treatment and oral gavage (to mimic consumption by food). Because live CPMV is used, an important question is whether there is any evidence of shedding of infectious particles from mice or patients. CPMV is noninfectious toward mammals; however, it is infectious toward plants including black-eyed peas and other legumes. Biodistribution data in tumor-bearing and healthy mice indicate little leaching from tumors and clearance via the reticuloendothelial system followed by biliary excretion. While there was evidence of shedding of RNA in stool, there was no evidence of infectious particles when plants were challenged with stool extracts, thus indicating agronomical safety. Together these data aid the translational development of CPMV as a drug candidate for cancer immunotherapy.

Hepatic Niemann-Pick C1-Like 1 exacerbates non-alcoholic fatty liver disease by re-absorbing specific biliary oxysterols

BackgroundDietary oxysterols are believed to be associated with the progression of non-alcoholic fatty liver disease (NAFLD). However, the molecular basis of the association between dietary oxysterols and NAFLD is poorly understood. We hypothesized that hepatic Niemann-Pick C1-Like 1 (NPC1L1), a cholesterol re-absorber from bile to the liver, would regulate hepatic oxysterol levels and affects NAFLD progression. Methods and resultsConsidering the species differences in hepatic NPC1L1 expression, we used liver-specific NPC1L1 transgenic (NPC1L1Tg) mice as a human model and demonstrated that oxysterol-rich heated cholesterol exacerbated high-fat diet-induced steatosis, an early stage of NAFLD, in a hepatic NPC1L1-dependent manner. Analyses of hepatic and biliary oxysterol levels in NPC1L1Tg mice and in vitro oxysterol uptake assays with NPC1L1-overexpressing cells revealed that NPC1L1 can uptake some, but not all, oxysterols and suppress their biliary excretion. Furthermore, in vitro and in vivo analyses revealed that 22(R)-hydroxycholesterol (22R-OHC) and 25-hydroxycholesterol (25-OHC), which are NPC1L1 substrates, were primarily involved in steatosis progression, via the activation of liver X receptor α and retinoid-related orphan receptor γ, respectively. Consistent with these results, examination of clinical specimens revealed that among the 14 major oxysterols analyzed, plasma concentrations of 22R-OHC and 25-OHC were significantly positively correlated with hepatic fat accumulation in humans. ConclusionsAmong the major dietary oxysterols, 22R-OHC and 25-OHC are particularly potent in promoting the progression of hepatic steatosis in a hepatic NPC1L1-dependent manner.

Aluminum, Arsenic, Beryllium, Cadmium, Chromium, Cobalt, Copper, Iron, Lead, Mercury, Molybdenum, Nickel, Platinum, Thallium, Titanium, Vanadium, and Zinc: Molecular Aspects in Experimental Liver Injury.

Experimental liver injury with hepatocelluar necrosis and abnormal liver tests is caused by exposure to heavy metals (HMs) like aluminum, arsenic, beryllium, cadmium, chromium, cobalt, copper, iron, lead, mercury, molybdenum, nickel, platinum, thallium, titanium, vanadium, and zinc. As pollutants, HMs disturb the ecosystem, and as these substances are toxic, they may affect the health of humans and animals. HMs are not biodegradable and may be deposited preferentially in the liver. The use of animal models can help identify molecular and mechanistic steps leading to the injury. HMs commonly initiate hepatocellular overproduction of ROS (reactive oxygen species) due to oxidative stress, resulting in covalent binding of radicals to macromolecular proteins or lipids existing in membranes of subcellular organelles. Liver injury is facilitated by iron via the Fenton reaction, providing ROS, and is triggered if protective antioxidant systems are exhausted. Ferroptosis syn pyroptosis was recently introduced as mechanistic concept in explanations of nickel (Ni) liver injury. NiCl2 causes increased iron deposition in the liver, upregulation of cyclooxygenase 2 (COX-2) protein and mRNA expression levels, downregulation of glutathione eroxidase 4 (GPX4), ferritin heavy chain 1 (FTH1), nuclear receptor coactivator 4 (NCOA4) protein, and mRNA expression levels. Nickel may cause hepatic injury through mitochondrial damage and ferroptosis, defined as mechanism of iron-dependent cell death, similar to glutamate-induced excitotoxicity but likely distinct from apoptosis, necrosis, and autophagy. Under discussion were additional mechanistic concepts of hepatocellular uptake and biliary excretion of mercury in exposed animals. For instance, the organic anion transporter 3 (Oat3) and the multidrug resistance-associated protein 2 (Mrp2) were involved in the hepatic handling of mercury. Mercury treatment modified the expression of Mrp2 and Oat3 as assessed by immunoblotting, partially explaining its impaired biliary excretion. Concomitantly, a decrease in Oat3 abundance in the hepatocyte plasma membranes was observed that limits the hepatic uptake of mercury ions. Most importantly and shown for the first time in liver injury caused by HMs, titanium changed the diversity of gut microbiota and modified their metabolic functions, leading to increased generation of lipopolysaccharides (LPS). As endotoxins, LPS may trigger and perpetuate the liver injury at the level of gut-liver. In sum, mechanistic and molecular steps of experimental liver injury due to HM administration are complex, with ROS as the key promotional compound. However, additional concepts such as iron used in the Fenton reaction, ferroptosis, modification of transporter systems, and endotoxins derived from diversity of intestinal bacteria at the gut-liver level merit further consideration.

Pharmacokinetic of berberine, the main constituent of Berberis vulgaris L.: A comprehensive review.

Barberry (Berberis vulgaris L.) is a medicinal plant and its main constituent is an isoquinoline alkaloid named berberine that has multiple pharmacological effects such as antioxidant, anti-microbial, antiinflammatory, anticancer, anti-diabetes, anti-dyslipidemia, and anti-obesity. However, it has restricted clinical uses due to its very poor solubility and bioavailability (less than 1%). It undergoes demethylenation, reduction, and cleavage of the dioxymethylene group in the first phase of metabolism. Its phase two reactions include glucuronidation, sulfation, and methylation. The liver is the main site for berberine distribution. Berberine could excrete in feces, urine, and bile. Fecal excretion of berberine (11-23%) is higher than urinary and biliary excretion routes. However, a major berberine metabolite is excreted in urine greater than in feces. Concomitant administration of berberine with other drugs such as metformin, cyclosporine A, digoxin, etc. may result in important interactions. Thus, in this review, we gathered and dissected any related animal and human research articles regarding the pharmacokinetic parameters of berberine including bioavailability, metabolism, distribution, excretion, and drug-drug interactions. Also, we discussed and gathered various animal and human studies regarding the developed products of berberine with better bioavailability and consequently, better therapeutic effects.

Design and conduct considerations for studies in patients with hepatic impairment.

Despite the liver being the primary site for clearance of xenobiotics utilizing a myriad of mechanisms ranging from cytochrome P450 enzyme pathways, glucuronidation, and biliary excretion, there is a dearth of information available as to how the severity of hepatic impairment (HI) can alter drug absorption and disposition (i.e., pharmacokinetics [PK]) as well as their efficacy and safety or pharmacodynamics (PD). In general, regulatory agencies recommend conducting PK studies in subjects with HI when hepatic metabolism/excretion accounts for more than 20% of drug elimination or if the drug has a narrow therapeutic range. In this tutorial, we provide an overview of the global regulatory landscape, clinical measures for hepatic function assessment, methods to stage HI severity, and consequently the impact on labeling. In addition, we provide an in-depth practical guidance for designing and conducting clinical trials for patients with HI and on the application of modeling and simulation strategies in lieu of dedicated trials for dosing recommendations in patients with HI.

Gadoxetic acid-enhanced MRI-derived functional liver imaging score (FLIS) and spleen diameter predict outcomes in ACLD.

Functional liver imaging score (FLIS) - derived from gadoxetic acid-enhanced MRI - correlates with liver function and independently predicts liver-related mortality in patients with chronic liver disease (CLD), while splenic craniocaudal diameter (SCCD) is a marker of portal hypertension. The aim of this study was to investigate the accuracy of a combination of FLIS and SCCD for predicting hepatic decompensation, acute-on-chronic liver failure (ACLF), and mortality in patients with advanced CLD (ACLD). We included 397 patients with CLD who underwent gadoxetic acid-enhanced liver MRI. The FLIS was calculated by summing the points (0-2) of 3 hepatobiliary-phase features: hepatic enhancement, biliary excretion, and portal vein signal intensity. Patients were stratified into 3 groups according to liver fibrosis severity and presence/history of hepatic decompensation: non-ACLD, compensated ACLD (cACLD), and decompensated ACLD (dACLD). SCCD showed excellent intra- and inter-reader agreement. Importantly, SCCD was an independent risk factor for hepatic decompensation in patients with cACLD (per cm; adjusted hazard ratio [aHR] 1.13; 95% CI 1.04-1.23; p= 0.004). Patients with cACLD and a FLIS of 0-3 points and/or a SCCD of >13cm were at increased risk of hepatic decompensation (aHR 3.07; 95% CI 1.43-6.59; p= 0.004). In patients with dACLD, a FLIS of 0-3 was independently associated with an increased risk of ACLF (aHR 2.81; 95% CI 1.16-6.84; p= 0.02), even after adjusting for other prognostic factors. Finally, a FLIS and SCCD-based algorithm was independently predictive of transplant-free mortality and stratified the probability of transplant-free survival (TFS) in ACLD (p <0.001): FLIS 4-6 and SCCD ≤13cm (5-year TFS of 84%) vs. FLIS 4-6 and SCCD >13cm (5-year TFS of 70%) vs. FLIS 0-3 (5-year TFS of 24%). The FLIS and SCCD are simple imaging markers that provide complementary information for risk stratification in patients with compensated and decompensated ACLD. Magnetic resonance imaging (MRI) can be used to assess the state of the liver. Previously the functional liver imaging score, which is based on MRI criteria, was developed as a measure of liver function and to predict the risk of liver-related complications or death. By combining this score with a measurement of spleen diameter, also using MRI, we generated an algorithm that could predict the risk of adverse liver-related outcomes in patients with advanced chronic liver disease.

S2948 Challenges in Recognizing and Diagnosing Wilson Disease

Introduction: Wilson disease is a rare autosomal recessive disease leading to impaired copper homeostasis and accumulation in the liver, brain, and other organs. It is manageable, and physicians must familiarize themselves with the diversity of its presentation. Our case sheds light on the challenges; health care providers face in establishing the diagnosis. Case Description/Methods: A fifty-eight-year-old female was admitted to the hospital for altered mental status who had a dramatic hospital course with acute liver failure complicated by shock and multiorgan failure. Her past medical history is significant for COPD, liver cirrhosis. Family history is positive for Alpha-1 Antitrypsin deficiency. She presented with acute psychosis and altered mental status. Patient was admitted with suspected hepatic encephalopathy. She developed acute liver failure followed by shock and multiorgan failure. Her work up came back as Hg 6.7, Plt 27, INR 2.1, Haptoglobin < 8 mg/dl, Coombs negative, Ceruoplasmn 5.9, copper serum 32, 24 hours urine copper level 42 and urine copper level 351. Previously, she complained of tremor and slurred speech. She was evaluated by neurology team for seizure like activity, but it was found that her movements were compelling choreiform movements (Figure). Liver cirrhosis evaluation started on 2019 when she was evaluated for new onset ascites. Her exam showed abdominal distension and lower limb edema, labs showed ALP 247, AST/ALT 51/16, total bilirubin 0.7, ANA >1: 1280, alpha 1 antitrypsin low 72 with MZ phenotype, Ceruplasmin level 13. Liver Biopsy Showed findings consistent with moderately active steatohepatitis with cirrhosis. It was presumed that her liver cirrhosis was related to A-1AT deficiency/NASH. The low ceruplasmin has slipped and the diagnosis of Liver Cirrhosis secondary to A-1AT deficiency carried on. Discussion: Wilson disease caused by mutations in the ATP7B gene responsible for intracellular copper transporter's function, led to impairment in biliary copper excretion leading to the deposit of copper in several organs. The diagnosis is based on the score developed at the 8th International Meeting on Wilson Disease in Leipzig (8). If the score is ≥4, Wilson disease is highly likely. In our patient, points are given as follows: Neuropsychiatric symptoms suggestive of Wilson disease (2), Coombs-negative hemolytic anemia with high serum copper (1), Serum ceruloplasmin < 10 mg/dL (2) with a total score of 5 points, which made her diagnosis with Wilson disease is highly likely.Figure 1.: Kayser-Fleisher ring.

S1818 Rare Sequelae of Obstructive Jaundice: Hyperferritinemia and Bile Cast Nephropathy

Introduction: Obstructive jaundice occurs due to a physical blockage in the biliary outflow tract or external compression. While jaundice and scleral icterus are common symptoms initially, long term sequelae include severe systemic manifestations from the buildup of various compounds normally excreted in bile such as bilirubin. Case Description/Methods: A 67-year-old male smoker presented with 3 weeks of pruritus, acholic stools, dark urine, nausea, vomiting, and 20-pound weight loss. Physical exam was notable for jaundice and scleral icterus, LUQ and epigastric tenderness to palpation, but lacked hepatosplenomegaly, ascites or other stigmata of cirrhosis. Liver function tests showed AST 486 IU/L, Alk Phos 1419 IU/L, Alt 600 IU/L, and total bilirubin >30.0 mg/dL with direct bilirubin >10.0 mg/dL. Ferritin was >7500 ng/mL with decreased transferrin of 159 mcg/dL. Hepatitis panel and malignancy/autoimmune markers were negative. CMP showed BUN 74 mg/dL, and creatinine 5.1 mg/dL with 2+bilirubin on urinalysis and microscopic analysis showing pigmented renal tubular cells, bilirubin crystals, and waxy casts suggestive of ATN due to bilirubin damage and possible CKD given waxy casts (Table). CT abdomen reported severe intra and extra hepatic biliary duct dilation with CBD of 17 mm and abrupt tapering with pancreatic head fullness confirmed with MRCP. On day 2, ERCP showed a tight 15mm distal biliary stricture. A small sphincterotomy followed by balloon dilation allowed for placement of a CBD stent with excellent drainage of dark green bile. Following ERCP, patient had a drop of liver function tests and ferritin levels, gradual improvement in BUN and creatinine, and was discharged in stable condition on hospital day 6. On day 16, EUS revealed a hypoechoic area within the periampullary area with atypical cells in brushings collected during repeat ERCP (Figure). Discussion: Iron and iron binding proteins have been shown to be excreted in bile, primarily in iron excess. Our patient showed a large increase in ferritin signifying the potential role of biliary excretion of excess ferritin, with unknown ramifications. Additionally, severe biliary tree obstruction led to markedly elevated bilirubin, overwhelming renal clearance leading to severe tubular damage. With alleviation of obstruction, there was a steady decrease in ferritin and return to normal baseline renal function. Further research is needed to clarify both the consequences of excess ferritin in biliary obstruction and the significance of excess bilirubin in renal injury.Figure 1.: a) Ampulla prior to ERCP on day 2 shows no periampullary abnormality. b) Day 16 - Endoscopic Ultrasound showing narrowing of distal common bile duct with hypoechoic intraductal area. c) Bile casts and bilirubin crystals seen on microscopy. Table 1. - Patient’s Laboratory test results on and post admission Laboratory Values Reference Range Day 1 Day 5 (3 days post-ERCP) Day 21 AST 13 – 39 IU/L 486 187 18 ALT 7 – 52 IU/L 600 315 27 Alkaline Phosphatase 34 – 104 IU/L 1419 886 160 Total Bilirubin 0.3 - 1.2 mg/dL >30.0 13.0 4.4 Albumin 3.5 - 5.2 g/ 3.0 2.9 3.4 BUN 7 – 25 mg/dL 74 64 18 Creatinine 0.5 - 1.2 mg/dL 5.1 2.90 1.01 WBC 4 – 11 K/cmm 13.8 17.7 10.1 Hgb 13.7 - 17.5 g/dL 11.9 9.4 8.5 Ferritin 24 – 336 >7500 4677 976 Transferrin 300 to 360 mcg/dL 159 233 Iron 50 - 182 ug/dL 126 61 Iron Saturation 57% 19% TIBC 250 – 450 ug/dl 233 326 Urine Bilirubin Negative 2+ Negative Urobilinogen 0.0 - 2.0 EU/dL 4.0 < 2.0 PT 9.1 - 13.2 sec 26.6 12.8 PTT 23.3 - 36.6 SEC 42.0 33.0 INR 0.8 - 1.2 2.3 1.1 Alpha-1-Antitrypsin (ATT) 83 – 199 mg/dL 256 Ceruloplasmin 18– 36 mg/dL 51 Carcinoembryonic Antigen (CEA) 0.0 - 3.0 ng/mL 3.9

Revisiting Quantification of Phenylalanine/Tyrosine Flux in the Ochronotic Pathway during Long-Term Nitisinone Treatment of Alkaptonuria.

Changes in the phenylalanine (PHE)/tyrosine (TYR) pathway metabolites before and during homogentisic acid (HGA)-lowering by nitisinone in the Suitability of Nitisinone in Alkaptonuria (AKU) 2 (SONIA 2) study enabled the magnitude of the flux in the pathway to be examined. SONIA 2 was a 48-month randomised, open-label, evaluator-blinded, parallel-group study performed in the UK, France and Slovakia recruiting patients with confirmed AKU to receive either 10 mg nitisinone or no treatment. Site visits were performed at 3 months and yearly thereafter. Results from history, photographs of eyes/ears, whole body scintigraphy, echocardiography and abdomen/pelvis ultrasonography were combined to produce the Alkaptonuria Severity Score Index (cAKUSSI). PHE, TYR, hydroxyphenylpyruvate (HPPA), hydroxyphenyllactate (HPLA) and HGA metabolites were analysed by liquid chromatography/tandem mass spectrometry in 24 h urine and serum samples collected before and during nitisinone. Serum metabolites were corrected for total body water (TBW), and the sum of 24 h urine plus total body water metabolites of PHE, TYR, HPPA, HPLA and HGA were determined. The sum of urine metabolites (PHE, TYR, HPPA, HPLA and HGA) were similar pre- and peri-nitisinone. The sum of TBW metabolites and sum TBW + URINE metabolites were significantly higher peri-nitisinone (p < 0.001 for both) compared with pre-nitisinone baseline. Significantly higher concentrations of metabolites from the tyrosine metabolic pathway were observed during treatment with nitisinone. Arguments for unmasking of the ochronotic pathway and biliary elimination of HGA are put forward.

Sinusoidal Organic Anion-Transporting Polypeptide 1B1/1B3 and Bile Canalicular Multidrug Resistance-Associated Protein 2 Play an Essential Role in the Hepatobiliary Disposition of a Synthetic Cyclic Dinucleotide (STING Agonist)

The liver is central to the elimination of many drugs from the body involving multiple processes and understanding of these processes is important to quantitively assess hepatic clearance of drugs. The synthetic STING (STimulator of INterferon Genes protein) agonist is a new class of drugs currently being evaluated in clinical trials as a potential anticancer therapy. In this study, we used ML00960317 (synthetic STING agonist) to investigate the hepatobiliary disposition of this novel molecular entity. A bile-duct cannulated (BDC) rat study indicated that biliary excretion is the major route of elimination for ML00960317 (84% of parent dose in bile). The human biliary clearance using in vitro sandwich cultured human hepatocyte model predicted significant biliary excretion of ML00960317 (biliary excretion index (BEI) of 47%). Moreover, the transport studies using transporter expressing cell lines, hepatocytes, and membrane vesicles indicated that ML00960317 is a robust substrate of OATP1B1, OATP1B3, and MRP2. Using relative expression factor approach, the combined contribution of OATP1B1 (fraction transported (ft) = 0.62) and OATP1B3 (ft = 0.31) was found to be 93% of the active uptake clearance of ML00960317 into the liver. Furthermore, OATP1B1 and OATP1B3-mediated uptake of ML00960317 was inhibited by rifampicin with IC50 of 6.5 and 2.3 μM, respectively indicating an in vivo DDI risk (R value of 1.5 and 2.5 for OATP1B1 and OATP1B3, respectively). These results highlighted an important role of OATP1B1, OATP1B3, and MRP2 in the hepatobiliary disposition of ML00960317. These pathways may act as rate-determining steps in the hepatic clearance of ML00960317 thus presenting clinical DDI risk.Graphical

Ion Exchange Biomaterials to Capture Daptomycin and Prevent Resistance Evolution in Off-Target Bacterial Populations.

Daptomycin (DAP), a cyclic anionic lipopeptide antibiotic, is among the last resorts to treat multidrug-resistant Gram-positive bacterial infections, caused by vancomycin-resistant Enterococcus faecium or methicillin-resistant Staphylococcus aureus. DAP is administered intravenously, and via biliary excretion, ∼5-10% of the intravenous DAP dose arrives in the gastrointestinal (GI) tract where it drives resistance evolution in the off-target populations of E. faecium bacteria. Previously, we have shown in vivo that the oral administration of cholestyramine, an ion exchange biomaterial (IXB) sorbent, prevents DAP treatment from enriching DAP resistance in the populations of E. faecium shed from mice. Here, we investigate the biomaterial-DAP interfacial interactions to uncover the antibiotic removal mechanisms. The IXB-mediated DAP capture from aqueous media was measured in controlled pH/electrolyte solutions and in the simulated intestinal fluid (SIF) to uncover the molecular and colloidal mechanisms of DAP removal from the GI tract. Our findings show that the IXB electrostatically adsorbs the anionic antibiotic via a time-dependent diffusion-controlled process. Unsteady-state diffusion-adsorption mass balance describes the dynamics of adsorption well, and the maximum removal capacity is beyond the electric charge stoichiometric ratio because of DAP self-assembly. This study may open new opportunities for optimizing cholestyramine adjuvant therapy to prevent DAP resistance, as well as designing novel biomaterials to remove off-target antibiotics from the GI tract.

Laparoscopic revision of Kasai portoenterostomy after initial laparoscopic portoenterostomy in patients with biliary atresia: a limited but positive effect on native liver survival.

It is important for patients with biliary atresia (BA) to retain the native liver after Kasai portoenterostomy (PE). Laparoscopic PE (Lap-PE) is standard, whereas laparoscopic revision of PE (Lap-revision) is performed as needed. We report the medium-term outcomes of Lap-revision. We retrospectively reviewed the demographics and outcomes of 63 patients who underwent Lap-PE between 2013 and 2021. Indications for revision included recurrent jaundice, repeat cholangitis, and persistent jaundice with temporary biliary excretion following the initial PE. We compared liver transplantation (LT) data of patients who underwent Lap-revision with those of patients who did not. Lap-revision was performed in 20 patients. Of those 17 (excluding the two who were jaundice-free before the age of 1, and the one who underwent open conversion for bleeding), 11 (65%) were jaundice-free 1year after Lap-revision. The surgical parameters of LT did not differ between patients who underwent Lap-revision and those who did not. Lap-revision for patients with BA had a limited but positive effect on native liver survival and did not adversely affect subsequent LT. Therefore, Lap-revision could be second-line standard therapy in patients with BA who have demonstrated biliary drainage at least once after initial PE.

Novel Plant Extract Ameliorates Metabolic Disorder through Activation of Brown Adipose Tissue in High-Fat Diet-Induced Obese Mice.

Obesity is characterized by excessive body fat accumulation due to unbalanced energy intake and expenditure. Potential therapeutic targets for anti-obesity include the inhibition of white adipose tissue (WAT) hypertrophy and hyperplasia and the activation of brown adipose tissue (BAT). Not only the activation of BAT but also the browning of WAT have gained increasing attention in research fields as an alternative method in the prevention and treatment of obesity. Here, we investigated possible mechanisms underlying the anti-obesity effect of Phlomis umbrosa Turcz. root ethanol extract (PUE) in an obesogenic animal model. PUE treatment can reduce diet-induced obesity and modulate obesity-associated metabolic disorders, including insulin resistance, hepatic steatosis, and inflammation. In the liver, PUE improved hepatic steatosis by suppressing hepatic lipogenesis and lipid absorption while increasing biliary sterol excretion and hepatic fatty acid oxidation compared to the high-fat group. Moreover, PUE increased energy expenditure and regulated fecal lipid excretion, leading to reduced body weight gain. In particular, PUE remarkably activated the browning of subWAT via upregulation of the browning-related protein and gene expression and promoted BAT activation. In conclusion, these findings provide the potential therapeutic usefulness into the effects of PUE in the treatment of obesity and metabolic disorders. Furthermore, it suggests that PUE treatment can regulate energy metabolism via activating BAT and browning subWAT.

Portal hypertension may influence the registration of hypointensity of small hepatocellular carcinoma in the hepatobiliary phase in gadoxetic acid MR.

BackgroundThe aim of the study was to analyze the association between the liver uptake of Gadolinium-ethoxybenzyl-diethylenetriamine penta-acetic acid (Gd-EOB-DTPA) in the hepatobiliary phase (HBP) in cirrhotic patients and the presence of clinically significant portal hypertension (CSPH), and how these features impact on hepatocellular carcinoma (HCC) detection in the HBP.Patients and methodsPost-hoc analysis of a prospective cohort of 62 cirrhotic patients with newly US-detected nodule between 1–2 cm (study group). Twenty healthy subjects were used as control group. Qualitative and quantitative analysis of the liver contrast uptake in the HBP assessed by Relative Liver-Enhancement (RLE), Liver-Spleen (LSCR), Liver-Muscle (LMCR), and Liver-Kidney Contrast-Ratio (LKCR), Contrast Enhancement Index (CEI), and Hepatic Uptake (HUI), and biliary excretion, were registered. CSPH was confirmed invasively (HVPG > 10 mmHg) or by indirect parameters. The appearance of HCC at the HBP was analyzed.ResultsNineteen patients (30.6%) did not have CSPH. In 41 patients (66.1%) the final diagnosis was HCC. All indices were significantly higher in the control group, indicating a more intense HBP liver signal intensity compared to patients with cirrhosis, even if the comparison was restricted to patients with no CSPH. CSPH was associated to a lower rate of HCC hypointensity in the HBP (51.9% vs. 85.7% without CSPH, p = 0.004).ConclusionsLiver uptake of Gd-EOB-DTPA at the HBP is decreased in cirrhosis even if the liver function is minimally impaired and it falls down significantly in patients with CSPH compromising the recognition of hypointense lesions. This fact may represent a limitation for the detection of small HCC in patients with cirrhosis and CSPH.

Phenotypic polymorphism in Wilson’s disease – between genetics and epigenetics

Background: Wilson’s disease is a rare, autosomal recessive genetic disorder that affects the biliary excretion of copper and its toxic accumulation in various tissues, especially the liver and brain. It is widespread throughout the world, with a high prevalence in socio-culturally isolated communities. The course of the disease and the age of onset depend on the site of mutation in the gene and the degree of functional impairment of the ATP7B protein. The presence of the compound heterozygous patient complicates the comparative genetic and clinical evaluation. Therefore, it is necessary to analyze Wilson’s variants in both the homozygous and the compound-heterozygous conditions to better understand the genotype-phenotype correlations and the incomplete penetrance observed in this disorder. Outlining clear phenotype-genotype associations is difficult due to a large number of mutations and different clinical presentations, but the involvement of epigenetic factors, modifying genes, environmental and lifestyle factors could explain the differences in evolution and onset in members of the same family and not only. Conclusions: Wilson’s disease is a genetically and clinically complex disorder. Although the results of genotype-phenotype correlation studies are not well defined, and in some cases are completely contradictory, some peculiarities related to the age of onset, sex, clinical phenotype, and the evolution of the disease have been highlighted. The interaction between genetic mutations and epigenetic factors may explain the phenotypic variability, but needs further study.

A simple and sensitive HPLC-FL method for bioanalysis of velpatasvir, a novel hepatitis C virus NS5A inhibitor, in rat plasma: Investigation of factors determining its oral bioavailability

Velpatasvir is a novel inhibitor of hepatitis C virus nonstructural protein 5A that received US Food and Drug Administration approval for the treatment of patients with chronic hepatitis C virus genotypes 1–6. In the present study, a sensitive bioanalytical method for velpatasvir was developed using high-performance liquid chromatography coupled with a fluorescence detector system, which was applied to elucidate the factors determining the oral bioavailability and disposition of velpatasvir. This method offered sufficient sensitivity, with a lower limit of quantification of 0.5 ng/mL, which is comparable to previously reported methods using liquid chromatography coupled with tandem mass spectrometry. Velpatasvir exhibited low oral bioavailability, moderate intestinal permeability, and significant biliary excretion in rats. It was also found to be significantly metabolized in the liver, with a low-to-moderate extraction ratio; however, its intestinal metabolism and enterohepatic circulation did not occur. Thus, our present results demonstrate that the oral bioavailability of velpatasvir is primarily dependent on gut absorption and hepatic first-pass metabolism. The fractions of velpatasvir dose unabsorbed from the gut and eliminated by the liver before reaching the systemic circulation following oral administration were estimated to be 32.8%–58.6% and 4.74%–30.54% of the oral dose, respectively. To our knowledge, this is the first systematic study to investigate the contributory roles of biopharmaceutical and pharmacokinetic factors on the oral bioavailability of velpatasvir, together with a new bioanalytical method for velpatasvir.

Monocrotaline Toxicity Alters the Function of Hepatocyte Membrane Transporters in Rats.

Pyrrolizidine alkaloid monocrotaline (MCT) induces sinusoidal obstruction syndrome (SOS) in rats characterised by a sinusoidal congestive obstruction. Additionally, MCT administration decreases the biliary excretion of gadobenate dimeglumine (BOPTA), a hepatobiliary substrate used in clinical imaging. BOPTA crosses hepatocyte membranes through organic anion transporting polypeptides, multidrug-resistance-associated protein 2, and Mrp3/4 transporters, and a modified function of these transporters is likely to explain the decreased biliary excretion. This study compared BOPTA transport across hepatocytes in livers isolated from normal (Nl) rats and rats with intragastric administration of MCT. BOPTA hepatocyte influx clearance was similar in both groups, while biliary clearance and bile concentrations were much lower in MCT than in Nl livers. BOPTA efflux clearance back to the sinusoids compensated for the low biliary excretion, and hepatocyte concentrations remained similar in both groups. This SOS-associated changes of transporter functions might impact the pharmacokinetics of numerous drugs that use similar transporters to cross hepatocytes.

Elucidation of clearance mechanism of TP0463518, a novel hypoxia-inducible factor prolyl hydroxylase inhibitor: does a species difference in excretion routes exist between humans and animals?

TP0463518, a novel hypoxia-inducible factor prolyl hydroxylase inhibitor, is reportedly excreted predominantly through urinary excretion in an unchanged form in humans, with partial biliary excretion also possible. However, the clearance mechanisms remain unclear. The aim of this study was to investigate the clearance mechanisms in humans and to assess species differences in the excretion routes. TP0463518 was not metabolized in rat, dog, or human hepatocytes. TP0463518 is a substrate for human BCRP, OATP1B1, OATP1B3, and OAT3, suggesting that renal uptake by OAT3 is probably the predominant clearance route, with hepatic uptake by OATP1B1 and OATP1B3 contributing partially to clearance in humans. A species difference in excretion routes was observed. The unchanged urinary excretion rates in humans, male rats, female rats, dogs, and monkeys were 80.7%, 0.1%, 40.9%, 15.2%, and 72.6%, respectively. Urinary excretion was predominant in humans and monkeys, while only biliary excretion was observed in male rats. Uptake studies using hepatocytes showed that the hepatic uptake clearance in rats was 13.6-fold higher than that in humans. Therefore, not only reabsorption via renal tubules, but also hepatic uptake seems to be involved in the species differences in excretion routes between rats and humans.