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Background and Purpose: The ATP‐dependent biliary efflux transporter ABCC2, also known as multidrug resistance protein 2 (MRP2), is essential for the cellular disposition and detoxification of various xenobiotics including drugs as well as endogenous metabolites. Common functionally relevant ABCC2 genetic variants significantly alter drug responses and contribute to side effects. The aim of this study was to determine functional consequences of rare variants identified in subjects with European ancestry using in silico tools and in vitro analyses. Experimental Approach: Targeted next‐generation sequencing of the ABCC2 gene was used to identify novel variants in European subjects (n = 143). Twenty‐six in silico tools were used to predict functional consequences. For biological validation, transport assays were carried out with membrane vesicles prepared from cell lines overexpressing the newly identified ABCC2 variants and estradiol β‐glucuronide and carboxydichlorofluorescein as the substrates. Key Results: Three novel rare ABCC2 missense variants were identified (W227R, K402T, V489F). Twenty‐five in silico tools predicted W227R as damaging and one as potentially damaging. Prediction of functional consequences was not possible for K402T and V489F and for the common linked variants V1188E/C1515Y. Characterisation in vitro showed increased function of W227R, V489F and V1188E/C1515Y for both substrates, whereas K402T function was only increased for carboxydichlorofluorescein. Conclusion and Implications: In silico tools were unable to accurately predict the substrate‐dependent increase in function of ABCC2 missense variants. In vitro biological studies are required to accurately determine functional activity to avoid misleading consequences for drug therapy. [ABSTRACT FROM AUTHOR]

Oleanolic acid (OA) is a naturally occurring pentacyclic triterpene compound that has been reported to cause cholestatic liver injury. However, the regulation and pathogenic role of bile acids in OA‐induced development of cholestatic liver injury remains largely unclear. Farnesoid X receptor (FXR) is a metabolic nuclear receptor that plays an important role in bile acid homeostasis in the liver by regulating efflux transporters bile salt export pump (BSEP) and multidrug resistance‐associated protein 2 (MRP2). The aim of this study was to investigate the effect of OA on hepatocyte tight junction function and determine the role of FXR, BSEP, and MRP2 in the mechanism of impairment of transport of bile acids induced by OA. Both in vivo and in vitro models were used to characterize the OA‐induced liver injury. The liquid chromatography–tandem mass spectrometry (LC‐MS) was employed to characterize the efflux function of the transporters, and the results showed that OA caused a blockage of bile acids efflux. OA treatment resulted in decreased expression levels of the tight junction proteins zonula occludens‐1 and occludin. Immunofluorescence results showed that OA treatment significantly reduced the number of bile ducts and the immunofluorescence intensity. Pretreatment with agonists of FXR and MRP2, respectively, in animal experiments attenuated OA‐induced liver injury, while pretreatment with inhibitors of BSEP and MRP2 further aggravated OA‐induced liver injury. These results suggest that OA inhibits FXR‐mediated BSEP and MRP2, leading to impaired bile acid efflux and disruption of tight junctions between liver cells, resulting in liver damage. Oleanolic acid (OA) is a naturally occurring pentacyclic triterpene compound that has been reported to cause cholestatic liver injury. In this study, OA inhibits FXR‐mediated BSEP and MRP2, leading to impaired bile acid efflux and disruption of tight junctions between liver cells, resulting in liver damage. Activation of FXR and MRP2 mitigated OA‐induced liver injury, while inhibition of BSEP and MRP2 further aggravated OA‐induced liver injury. [ABSTRACT FROM AUTHOR]

The aim of this review is to explore how diet and dietary supplements influence the activity of key multidrug resistance (MDR) transporters—MRP2, BCRP, and P-gp. These transporters play a crucial role in drug efflux from cancer cells and significantly affect chemotherapy outcomes. This review focuses on how dietary phytochemicals, such as catechins and quercetin, impact the expression and function of these transporters. Both in vitro and in vivo experiments were examined to assess changes in drug bioavailability and intracellular drug accumulation. The findings show that certain dietary components—such as catechins, flavonoids, resveratrol, curcumin, terpenoids, sterols, and alkaloids—can either inhibit or induce MDR transporter activity, thus influencing the effectiveness of chemotherapy. These results highlight the importance of understanding diet–drug interactions in cancer therapy to improve treatment outcomes and reduce side effects. In conclusion, dietary modifications and supplements should be carefully considered in cancer treatment plans to optimize therapeutic efficacy.

The endogenous metabolite of estradiol, estradiol 17β-D-glucuronide (E17G), is considered the main responsible of the intrahepatic cholestasis of pregnancy. E17G alters the activity of canalicular transporters through a signaling pathway-dependent cellular internalization, phenomenon that was attributed to oxidative stress in different cholestatic conditions. However, there are no reports involving oxidative stress in E17G-induced cholestasis, representing this the aim of our work. Using polarized hepatocyte cultures, we showed that antioxidant compounds prevented E17G-induced Mrp2 activity alteration, being this alteration equally prevented by the NADPH oxidase (NOX) inhibitor apocynin. The model antioxidant N -acetyl-cysteine prevented, in isolated and perfused rat livers, E17G-induced impairment of bile flow and Mrp2 activity, thus confirming the participation of reactive oxygen species (ROS) in this cholestasis. In primary cultured hepatocytes, pretreatment with specific inhibitors of ERK1/2 and p38MAPK impeded E17G-induced ROS production; contrarily, NOX inhibition did not affect ERK1/2 and p38MAPK phosphorylation. Both, knockdown of p47phox by siRNA and preincubation with apocynin in sandwich-cultured rat hepatocytes significantly prevented E17G-induced internalization of Mrp2, suggesting a crucial role for NOX in this phenomenon. Concluding, E17G-induced cholestasis is partially mediated by NOX-generated ROS through internalization of canalicular transporters like Mrp2, being ERK1/2 and p38MAPK necessary for NOX activation. [Display omitted] • Estradiol 17β- d glucuronide (E17G) elevates reactive oxygen species (ROS) in hepatocytes. • ROS participate in E17G-induced internalization of canalicular Mrp2. • ERK1/2 and p38MAPK are necessary for E17G-induced, NOX-dependent elevation of ROS. • N -acetyl-cysteine prevents E17G-induced cholestasis in isolated perfused rat livers. [ABSTRACT FROM AUTHOR]

P-glycoprotein (P-gp), breast cancer resistance protein (BCRP) and multidrug resistance transporter 2 (MRP2) are efflux transporters involved in the absorption, excretion, and distribution of drugs. Bidirectional cell assays are recognized models for evaluating the potential of new drugs as substrates or inhibitors of efflux transporters. However, the assays are complicated by a lack of selective substrates and/or inhibitors, as well simultaneous expression of several efflux transporters in cell lines used in efflux models. This project aims to evaluate an in vitro efflux cell assay employing model substrates and inhibitors of P-gp, BCRP and MRP2 with knockout (KO) cell lines. The efflux ratios (ER) of P-gp (digoxin, paclitaxel), BCRP (prazosin, rosuvastatin), MRP2 (etoposide, olmesartan) and mixed (methotrexate, mitoxantrone) substrates were determined in wild-type C2BBe1 and KO cells. For digoxin and paclitaxel, the ER decreased to less than 2 in the cell lines lacking P-gp expression. The ER decreased to less than 3 for prazosin and less than 2 for rosuvastatin in the cell lines lacking BCRP expression. For etoposide and olmesartan, the ER decreased to less than 2 in the cell lines lacking MRP2 expression. The ER of methotrexate and mitoxantrone decreased in single- and double-KO cells without BCRP and MRP2 expression. These results show that KO cell lines have the potential to better interpret complex drug-transporter interactions without depending upon multi-targeted inhibitors or overlapping substrates. For drugs that are substrates of multiple transporters, the single- and double-KO cells may be used to assess their affinities for the different transporters. [ABSTRACT FROM AUTHOR]

Ursolic acid (UA), a pentacyclic triterpenoid, exhibits various pharmacological actions, such as anti-inflammation, anti-tumor, anti-diabetes, heart protection, and liver protection. However, the role of nuclear factor E2-related factor 2 (NRF2)-mediated regulation of uridine diphosphate glucuronosyltransferase (UGT2B7) and bile salt export pump (BSEP)/multidrug resistance-associated protein 2 (MRP2) in UA against cholestatic liver injury has not been cleared. The purpose of this study is to explore the effect of UA on cholestatic liver injury and its potential mechanism. The results of the liver pathology sections and blood biochemical indices demonstrated that UA significantly attenuated the cholestatic liver injury induced by alpha-naphthylisothiocyanate (ANIT) in a dose-dependent manner. The mRNA and protein levels of UGT2B7 and BSEP/MRP2 were remarkably increased in the liver of ANIT rats and HepG2 cells pretreated with UA, but this activation was suppressed with NRF2 silenced. In conclusion, our findings demonstrate that UA prevents cholestasis, which may be associated with NRF2-mediated regulation of UGT2B7, BSEP/MRP2. [ABSTRACT FROM AUTHOR]

Background: Cholestasis is a common pathological manifestation dominated by accumulation of potentially toxic biliary compounds. Na+-taurocholate cotransporting polypeptide (NTCP) plays a critical role in protection from cholestasis and can be targeted therapeutically. Chishao (Paeoniae Radix Rubra) is a clinically efficacious agent for treating cholestasis, but the underlying mechanism has not been fully clarified. Objective: To evaluate the effects of Chishao on the expression of NTCP in rats with alpha-naphthylisothiocyanate (ANIT)-induced cholestasis. Methods: Chishao extracts were obtained by water decoction. Cholestasis model induced by ANIT in rats were established. Thirty rats were divided into five groups: control group (C), ANIT model group (M), 10 g/kg Chishao group (LD), 20 g/kg Chishao group (MD) and 40 g/kg Chishao group (HD). The levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TB), direct bilirubin (DB), alkaline phosphatase (ALP) and total bile acid (TBA) were detected. The mRNA and protein expression of NTCP, multidrug resistance associated protein 2 (MRP2) and bile salt export pump (BSEP) were detected by reverse transcription qPCR and Western blotting respectively. To assess the effects of Chishao on NTCP, MRP2 and BSEP localized at the membrane of hepatocytes, an in vitro experiment involving primary hepatocytes was conducted via the utilization of laser scanning confocal microscopy. Results: The extracts of Chishao significantly improved serum ALT, AST, ALP, TB, DB and TBA (p < 0.05), especially ALP in the HD group (p < 0.01). The histological pathological findings were also reversed in LD, MD and HD groups. The mRNA level of MRP2 was significantly downregulated after treatment with ANIT, whereas it was reversed in MD and HD groups (p < 0.05). The mRNA expression of NTCP was significantly downregulated after ANIT treatment, but dramatically upregulated in the HD group. The expressions of BSEP and MRP2 were similar, but that of NTCP decreased after ANIT treatment, which was reversed significantly by Chishao extracts in a dose-dependent manner. The expression of NTCP in hepatocytes from rats increased dose-dependently after Chishao treatment in vitro. Conclusion: Chishao extracts can improve the serum and histological performances of intra-hepatic cholestasis caused by ANIT, probably by working on transport proteins in liver cell membranes. [ABSTRACT FROM AUTHOR]

Magnoliae Officinalis Cortex (MOC), an herbal drug, contains polyphenolic lignans mainly magnolol (MN) and honokiol (HK). Methotrexate (MTX), a critical drug for cancers and autoimmune deseases, is a substrate of multidrug resistance-associated protein 2 (MRP2) and breast cancer resistance protein (BCRP). This study investigated the effect of coadministration of MOC on the pharmacokinetics of MTX and relevant mechanisms. SpragueeDawley rats were orally administered MTX alone and with single dose (2.0 and 4.0 g/kg) and repeated seven doses of MOC (2.0 g/kg thrice daily for 2 days, the 7th dose given at 0.5 h before MTX). The serum concentrations of MTX were determined by a fluorescence polarization immunoassay. The results showed that a single dose of MOC at 2.0 g/kg significantly increased the AUC0-t and MRT of MTX by 352% and 308%, and a single dose at 4.0 g/kg significantly enhanced the AUC0-t and MRT by 362% and 291%, respectively. Likewise, repeated seven doses of MOC at 2.0 g/kg significantly increased the AUC0-t and MRT of MTX by 461% and 334%, respectively. Mechanism studies indicated that the function of MRP2 was significantly inhibited by MN, HK and the serum metabolites of MOC (MOCM), whereas BCRP was not inhibited by MOCM. In conclusion, coadministration of MOC markedly enhanced the systemic exposure and mean residence time of MTX through inhibiting the MRP2-mediated excretion of MTX. [ABSTRACT FROM AUTHOR]

It was suggested that L. reuteri FLRE5K1 can ameliorate acetaminophen(APAP) -induced hyperbilirubinemia. The Kunming mice were administrated intragastrically with L.reuteri FLRE5K1 for 7 consecutive days. After 7 days, the experimental mice were intraperitoneally injected with 500 mg/Kg APAP to establish the model. Then the mice were fasted but allowed access to water for 12 h. The results showed that L. reuteri FLRE5K1 could reduce the contents of total bilirubin, urea and creatinine in serum of mice. The analysis of pathological sections also showed that L.reuteri FLRE5K1 had a significant alleviating effect on the inflammation caused by APAP. Through molecular detection, it was found that L.reuteri FLRE5K1 could improve the expression level of Multidrug resistance associated protein 2(MRP2) in the liver, thus affecting the metabolism of bilirubin and relieving hyperbilirubinemia. This study fills the gap in the exploration of the mechanism of improving hyperbilirubinemia by probiotics, provides technical support for future adjuvant clinical therapy, and has good potential application value. [ABSTRACT FROM AUTHOR]

Background & aims: Excretory liver failure is frequently associated with poor prognosis in critically ill patients. It is characterized by the loss of canalicular membrane export pumps at the hepatocyte membrane. The membrane export pump Multidrug resistant-associated protein (MRP) 2 is pivotal in hepatocytes for brushed membrane morphology and transport of various metabolites. In addition, MRP2 anchoring proteins of the Ezrin/Radixin/Moesin (ERM) family are crucial for the correct MRP2 location, integration, and function in different tissues. In hepatocytes, altered ERM signaling is elementary for developing excretory liver failure. Methods: Polarized human HepaRG cells, primary human hepatocytes, and hepatocyte-specific Ezrin knockout mice are employed to investigate ERM expression and function in health and the bile duct ligation model of obstructive cholestasis. Results: ERM-scaffolding protein Ezrin has no relevant function in maintaining the canalicular structure in hepatocytes during health and disease. Conclusions: Homeostasis of the canalicular pole in hepatocytes is maintained exclusively by Radixin but not Ezrin, and Radixin dysfunction promotes cholestasis.

A new series of nitric oxide-releasing estra-1,3,5,16-tetraene analogs (NO-∆-16-CIEAs) was designed and synthesized as dual inhibitors for EGFR and MRP2 based on our previous findings on estra-1,3,5-triene analog NO-CIEA 17 against both HepG2 and HepG2-R cell lines. Among the target compounds, 14a (R-isomer) and 14b (S-isomer) displayed potent anti-proliferative activity against both HepG2 and HepG2-R cell lines in comparison to the reference drug erlotinib. Remarkably, compound 14a resulted in a prominent reduction in EGFR phosphorylation at a concentration of 1.20 µM with slight activity on the phosphorylation of MEK1/2 and ERK1/2. It also inhibits MRP2 expression in a dose-dependent manner with 24% inhibition and arrested the cells in the S phase of the cell cycle. Interestingly, compound 14a (estratetraene core) exhibited a twofold increase in anti-proliferative activity against both HepG2 and HepG2-R in comparison with the lead estratriene analog, demonstrating the significance of the designed ∆-16 unsaturation. The results shed a light on compound 14a and support further investigations to combat multidrug resistance in chemotherapy of hepatocellular carcinoma patients. [ABSTRACT FROM AUTHOR]

Idiosyncratic Drug-Induced Liver Injury (iDILI) represents an actual health challenge, accounting for more than 40% of hepatitis cases in adults over 50 years and more than 50% of acute fulminant hepatic failure cases. In addition, approximately 30% of iDILI are cholestatic (drug-induced cholestasis (DIC)). The liver's metabolism and clearance of lipophilic drugs depend on their emission into the bile. Therefore, many medications cause cholestasis through their interaction with hepatic transporters. The main canalicular efflux transport proteins include: 1. the bile salt export pump (BSEP) protein (ABCB11); 2. the multidrug resistance protein-2 (MRP2, ABCC2) regulating the bile salts' independent flow by excretion of glutathione; 3. the multidrug resistance-1 protein (MDR1, ABCB1) that transports organic cations; 4. the multidrug resistance-3 protein (MDR3, ABCB4). Two of the most known proteins involved in bile acids' (BAs) metabolism and transport are BSEP and MDR3. BSEP inhibition by drugs leads to reduced BAs' secretion and their retention within hepatocytes, exiting in cholestasis, while mutations in the ABCB4 gene expose the biliary epithelium to the injurious detergent actions of BAs, thus increasing susceptibility to DIC. Herein, we review the leading molecular pathways behind the DIC, the links with the other clinical forms of familial intrahepatic cholestasis, and, finally, the main cholestasis-inducing drugs. [ABSTRACT FROM AUTHOR]

The coordinated movement of organic anions (e.g., drugs, metabolites, signaling molecules, nutrients, antioxidants, gut microbiome products) between tissues and body fluids depends, in large part, on organic anion transporters (OATs) [solute carrier 22 (SLC22)], organic anion transporting polypeptides (OATPs) [solute carrier organic (SLCO)], and multidrug resistance proteins (MRPs) [ATP-binding cassette, subfamily C (ABCC)]. Depending on the range of substrates, transporters in these families can be considered multispecific, oligospecific, or (relatively) monospecific. Systems biology analyses of these transporters in the context of expression patterns reveal they are hubs in networks involved in interorgan and interorganismal communication. The remote sensing and signaling theory explains how the coordinated functions of drug transporters, drug-metabolizing enzymes, and regulatory proteins play a role in optimizing systemic and local levels of important endogenous small molecules. We focus on the role of OATs, OATPs, and MRPs in endogenous metabolism and how their substrates (e.g., bile acids, short chain fatty acids, urate, uremic toxins) mediate interorgan and interorganismal communication and help maintain and restore homeostasis in healthy and disease states. [ABSTRACT FROM AUTHOR]

Baicalin, an important flavonoid isolated from Scutellaria baicalensis Georgi, is a Chinese herb widely used in clinical practice. We previously reported the in vivo accumulation of baicalin in rats with intrahepatic cholestasis (IHC) after a single dose. However, the effects of the long-term administration of baicalin on its pharmacokinetics are unknown. Thus, we investigated the disposition of baicalin in normal rats and those with IHC after single and multiple consecutive administrations. In addition, we further investigated the effect of baicalin on multidrug resistance protein 2 (MRP2) in vivo to explore the underlying mechanism. In our study, the liquid chromatography-mass spectrometry (LC-MS) method established to determine baicalin concentrations in rat blood was simple, specific, and with linearity (R2 = 0.9980) in the range of 1.01–506.00 μg/mL. The relative standard deviations (RSD) for intra-day and inter-day precision were not more than 10.55%, and the intra-day and inter-day accuracies were 94.94%–109.13%. The recovery rate and stability were in line with the requirements of the quantitative analysis of biological samples as stated in the Chinese Pharmacopoeia (2020 Edition). Compared with that in normal rats, the Cmax and t1/2 increased significantly in EE-induced rats with IHC, whereas the clearance (CL) decreased after a single administration of baicalin. However, the area under the curve decreased, CL increased, and the t1/2 was shortened after the continuous administration of baicalin in the IHC rat model compared with the single administration of baicalin, and the pharmacokinetic characteristics were similar to those in normal rats. Moreover, MRP2 expression increased in rats with IHC with the continuous administration of baicalin. Continuous baicalin intervention could effectively reduce its accumulation in rats with IHC, and the mechanism may be attributed to its enhancement of MRP2 expression.

ObjectivesMicrovillus inclusion disease (MVID) is a severe form of neonatal diarrhea, caused mainly by mutations in MYO5B. Inactivating mutations in MYO5B causes depolarization of enterocytes in the small intestine, which gives rise to chronic, unremitting secretory diarrhea. While the pathology of the small intestine in MVID patients is well described, little is known about extraintestinal effects of MYO5B mutation.MethodsWe examined stomach, liver, pancreas, colon, and kidney in Navajo MVID patients, who share a single homozygous MYO5B-P660L (1979C>T p.Pro660Leu, exon 16). Sections were stained for markers of the apical membrane to assess polarized trafficking.ResultsNavajo MVID patients showed notable changes in H/K-ATPase-containing tubulovesicle structure in the stomach parietal cells. Colonic mucosa was morphologically normal, but did show losses in apical ezrin and Syntaxin 3. Hepatocytes in the MVID patients displayed aberrant canalicular expression of the essential transporters MRP2 and BSEP. The pancreas showed small fragmented islets and a decrease in apical ezrin in pancreatic ducts. Kidney showed normal primary cilia.ConclusionsThese findings indicate that the effects of the P660L mutation in MYO5B in Navajo MVID patients are not limited to the small intestine, but that certain tissues may be able to compensate functionally for alterations in apical trafficking.

We report a case of a patient with Dubin–Johnson syndrome confirmed by a genetic study. A 50-year-old woman who had symptoms of intermittent right upper quadrant abdominal pain was diagnosed with calculous cholecystitis at another institute and was presented to our hospital for a cholecystectomy. She had no history of liver disease, and her physical examination was normal. Abdominal computed tomography showed a gallbladder stone with chronic cholecystitis. During a laparoscopic cholecystectomy for cholecystitis, a smooth, black-colored liver was noted, and a liver biopsy was performed. The biopsy specimen showed coarse, dark brown granules in centrilobular hepatocytes via hematoxylin and eosin staining. We performed a genetic study using the blood samples of the patient. In the adenosine triphosphate-binding cassette subfamily C member 2 (ABCC2) mutation study, a missense mutation in exon 18 was noted. Based on the black-colored liver without nodularity, conjugated hyperbilirubinemia, the liver biopsy results of the coarse pigment in centrilobular hepatocytes, and the ABCC2 mutation, Dubin–Johnson syndrome was diagnosed. The patient was managed with conservative care using hepatotonics. One month after follow-up, total bilirubin and direct bilirubin remained in a similar range. Another follow-up was planned a month later, and the patient maintained her use of hepatotonics. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Dubin–Johnson syndrome (DJS) is a benevolent genetic disorder of the liver with autosomal inheritance. It is a rare disorder characterized by an increase in conjugated bilirubin and anomaly in coproporphyrin clearance. DJS is caused by deleterious mutations in the ABCC2 gene. A polymorphism in the ABCC2 gene causes malfunctions in its ability to regulate the efflux of different organic anions, such as bilirubin, from hepatocytes to the canaliculi. Multidrug resistance protein 2 (MRP2) encoded by the ABCC2 gene is one of the main regulators of the export of bilirubin to respective sites. ABCC2 gene mutations have widely drawn attention in the pathology of DJS in various populations. The ABCC2 gene was subjected to the National Center for Biotechnology Information (NCBI) database in 2020, and non-synonymous single-nucleotide polymorphisms (nsSNPs) and variants in untranslated regions were studied using different computational servers. SIFT, Protein variation effect analyzer, and PolyPhen-2 were used to retrieve the damaging Single-nucleotide polymorphisms (SNPs); PhD-SNP, SNPs&GO, and Protein Analysis Through Evolutionary Relationships were used to predict the association of nsSNPs with DJS; Mutation3D illustrated the location of variants in the protein; SNAP2, MutPred2, ELASPIC, and HOPE were used to predict the structural and functional effects of these mutations on MRP2 ; and I-mutant 3.0 and MuPro were used to determine the effects of polymorphism on the function of MRP2. In this study, 18,947 SNPs were screened from the NCBI database, followed by a series of refinement of variants using online available servers. We concluded that 41 ABCC2 gene variants are vital etiological candidates for DJS in humans. These 41 variants had highly damaging effects on the MRP2 protein, which may lead to deficient transportation capacity, thereby affecting the efflux of bilirubin across the canalicular membrane. In silico tools are an alternative approach for predicting the target SNPs. Hence, previously unreported variants can be considered strong etiological candidates for diseases related to MRP2. [ABSTRACT FROM AUTHOR]

Background: Hepatolithiasis (HL) is one of the common diseases in hepatobiliary surgery, and bile duct fibrosis is the key step in the pathogenesis of HL. Salvia miltiorrhiza (S. miltiorrhiza) has an inhibitory effect on bile duct fibrosis, but its molecular mechanism remains unclear. Objectives: Our research aimed to clarify the molecular mechanism of S. miltiorrhiza on HL. Materials and Methods: The rats were fed with salvianolic acid B and salvianolic acid B-free lithogenic diet (LD) for 4 weeks to observe the degree of bile duct fibrosis. The expression levels of TNF, IL1B, IL6, and MRP2 in HIBEC stimulated by taurodeoxycholic acid (TDCA) were measured by RT-qPCR and ELISA. E-cadherin and Vimentin expression in HIBEC was detected using immunofluorescence and Western blot. Cell proliferation was detected by CCK8. Results: The fibrosis of the bile duct was the key step of HL. The NF-κB pathway was activated and MRP2 was expressed low in intrahepatic biliary epithelial cells surrounding bile duct stones. Through experiments, salvianolic acid B (Sal B) delays HL via the NF-κB/MRP2 axis. Conclusion: In this research, we confirmed that salvianolic acid B inhibited the HL via the NF-κB/MRP2 axis. [ABSTRACT FROM AUTHOR]

Estradiol 17β- d -glucuronide (E 2 17G) induces cholestasis by triggering endocytosis and further intracellular retention of the canalicular transporters Bsep and Mrp2, in a cPKC- and PI3K-dependent manner, respectively. Pregnancy-induced cholestasis has been associated with E 2 17G cholestatic effect, and is routinely treated with ursodeoxycholic acid (UDCA). Since protective mechanisms of UDCA in E 2 17G-induced cholestasis are still unknown, we ascertained here whether its main metabolite, tauroursodeoxycholate (TUDC), can prevent endocytosis of canalicular transporters by counteracting cPKC and PI3K/Akt activation. Activation of cPKC and PI3K/Akt was evaluated in isolated rat hepatocytes by immunoblotting (assessment of membrane-bound and phosphorylated forms, respectively). Bsep/Mrp2 function was quantified in isolated rat hepatocyte couplets (IRHCs) by assessing the apical accumulation of their fluorescent substrates, CLF and GS-MF, respectively. We also studied, in isolated, perfused rat livers (IPRLs), the status of Bsep and Mrp2 transport function, assessed by the biliary excretion of TC and DNP-SG, respectively, and Bsep/Mrp2 localization by immunofluorescence. E 2 17G activated both cPKC- and PI3K/Akt-dependent signaling, and pretreatment with TUDC significantly attenuated these activations. In IRHCs, TUDC prevented the E 2 17G-induced decrease in apical accumulation of CLF and GS-MF, and inhibitors of protein phosphatases failed to counteract this protection. In IPRLs, E 2 17G induced an acute decrease in bile flow and in the biliary excretion of TC and DNP-SG, and this was prevented by TUDC. Immunofluorescence studies revealed that TUDC prevented E 2 17G-induced Bsep/Mrp2 endocytosis. TUDC restores function and localization of Bsep/Mrp2 impaired by E 2 17G, by preventing both cPKC and PI3K/Akt activation in a protein-phosphatase-independent manner. [Display omitted] [ABSTRACT FROM AUTHOR]

Acquired cisplatin resistance in cervical cancer therapy is principally caused by reduction in intracellular drug accumulation, which is exerted by hyperactivation of the oncogenic PI3K/Akt signaling axis and overexpression of cisplatin-exporter MRP2 along with prosurvival effectors NF-κB and IAPs in cervical cancer cells. These activated prosurvival signaling cascades drive drug efflux and evasion of apoptosis for rendering drug-resistant phenotypes. Our study challenges the PI3K/Akt axis in a cisplatin-resistant cervical cancer scenario with phenethylisothiocyanate (PEITC) for chemosensitization of SiHaR, a cisplatin-resistant sub-line of SiHa and 3-methylcholanthrene–induced cervical cancer mice models. SiHaR exhibited higher MRP2, p-AktThr308, NF-κB, XIAP, and survivin expressions which cumulatively compromised cisplatin retention capacity and accumulated PEITC better than SiHa. SiHaR appeared to favor PEITC uptake as its accumulation rates were found to be positively correlated with MRP2 expressions. PEITC treatment in SiHaR for 3 h prior to cisplatin exposure revived intracellular platinum levels, reduced free GSH levels, generated greater ROS, and altered mitochondrial membrane potential compared to SiHa. Western blot and immunofluorescence results indicated that PEITC successfully downregulated MRP2 in addition to suppressing p-AktThr308, XIAP, survivin, and NF-κB expressions. In mice models, administration of 5 mg/kg body-weight PEITC priming dosage prior to treatment with 3 mg/kg body-weight of cisplatin remediated cervical histology and induced tumor regression in contrast to the group receiving the same dosage of cisplatin only. This suggested PEITC as a potential chemosensitizing agent in light of acquired cisplatin resistance in cervical cancer and established its candidature for Phase I clinical trial. [ABSTRACT FROM AUTHOR]

Acquired cisplatin resistance in cervical cancer therapy is principally caused by reduction in intracellular drug accumulation, which is exerted by hyperactivation of the oncogenic PI3K/Akt signaling axis and overexpression of cisplatin-exporter MRP2 along with prosurvival effectors NF-κB and IAPs in cervical cancer cells. These activated prosurvival signaling cascades drive drug efflux and evasion of apoptosis for rendering drug-resistant phenotypes. Our study challenges the PI3K/Akt axis in a cisplatin-resistant cervical cancer scenario with phenethylisothiocyanate (PEITC) for chemosensitization of SiHaR, a cisplatin-resistant sub-line of SiHa and 3-methylcholanthrene–induced cervical cancer mice models. SiHaR exhibited higher MRP2, p-AktThr308, NF-κB, XIAP, and survivin expressions which cumulatively compromised cisplatin retention capacity and accumulated PEITC better than SiHa. SiHaR appeared to favor PEITC uptake as its accumulation rates were found to be positively correlated with MRP2 expressions. PEITC treatment in SiHaR for 3 h prior to cisplatin exposure revived intracellular platinum levels, reduced free GSH levels, generated greater ROS, and altered mitochondrial membrane potential compared to SiHa. Western blot and immunofluorescence results indicated that PEITC successfully downregulated MRP2 in addition to suppressing p-AktThr308, XIAP, survivin, and NF-κB expressions. In mice models, administration of 5 mg/kg body-weight PEITC priming dosage prior to treatment with 3 mg/kg body-weight of cisplatin remediated cervical histology and induced tumor regression in contrast to the group receiving the same dosage of cisplatin only. This suggested PEITC as a potential chemosensitizing agent in light of acquired cisplatin resistance in cervical cancer and established its candidature for Phase I clinical trial.

Although arsenic trioxide (arsenite, As(III)) has shown a remarkable efficacy in the treatment of acute promyelocytic leukemia patients, multidrug resistance is still a major concern for its clinical use. Multidrug resistance-associated protein 4 (MRP4), which belongs to the ATP-binding cassette (ABC) superfamily of transporters, is localized to the basolateral membrane of hepatocytes and the apical membrane of renal proximal tubule cells. Due to its characteristic localization, MRP4 is proposed as a candidate in the elimination of arsenic and may contribute to resistance to As(III). To test this hypothesis, stable HEK293 cells overexpressing MRP4 or MRP2 were used to establish the role of these two transporters in As(III) resistance. The IC50 values of As(III) in MRP4 cells were approximately 6-fold higher than those in MRP2 cells, supporting an important role for MRP4 in resistance to As(III). The capacity of MRP4 to confer resistance to As(III) was further confirmed by a dramatic decrease in the IC50 values with the addition of MK571, an MRP4 inhibitor, and cyclosporine A, a well-known broad-spectrum inhibitor of ABC transporters. Surprisingly, the sensitivity of the MRP2 cells to As(III) was similar to that of the parent cells, although insufficient formation of glutathione and/or Se conjugated arsenic compounds in the MRP2 cells might limit transport. Given that MRP4 is a major contributor to arsenic resistance in vitro, further investigation into the correlation between MRP4 expression and treatment outcome of leukemia patients treated with arsenic-based regimens is warranted.

Abstract Background 2,3,5,4′-tetrahydroxystilbence-2-O-β-D-glucoside (TSG) is a polyhydroxyphenolic compound, which exhibited a broad spectrum of pharmacological activities, such as anti-inflammatory, anti-depression, anti-oxidation and anti-atherosclerosis. However, the compound had poor bioavailability and the underlying absorption mechanisms had not been studied. Therefore, the purpose of this study was to investigate the intestinal absorption mechanism of TSG. Methods This study used Caco-2 cell monolayer model and single-pass intestinal perfusion model to explore the gastrointestinal absorption mechanisms of TSG. The effects of basic parameters such as drug concentration, time and pH on the intestinal absorption of TSG were analyzed by high performance liquid chromatography. The absorption susceptibility of TSG to three inhibitors, P-gp inhibitors verapamil hydrochloride and quinidine, and MRP2 inhibitor probenecid were also assessed. Results TSG was poorly absorbed in the intestines and the absorption of TSG in stomach is much higher than that in intestine. Both in vitro and in situ experiments showed that the absorption of TSG was saturated with increasing concentration and it was better absorbed in a weakly acidic environment pH 6.4. Moreover, TSG interacts with P-gp and MRP2, and TSG was not only the substrate of the P-gp and MRP2, but also affected the expression of P-gp and MRP2. Conclusions It was concluded that the gastrointestinal absorption the most unique active ingredient and considered as the mechanisms of TSG involved processes passive transport and the participation of efflux transporters.

A new series of nitric oxide-releasing estra-1,3,5,16-tetraene analogs (NO-∆-16-CIEAs) was designed and synthesized as dual inhibitors for EGFR and MRP2 based on our previous findings on estra-1,3,5-triene analog NO-CIEA 17 against both HepG2 and HepG2-R cell lines. Among the target compounds, 14a (R-isomer) and 14b (S-isomer) displayed potent anti-proliferative activity against both HepG2 and HepG2-R cell lines in comparison to the reference drug erlotinib. Remarkably, compound 14a resulted in a prominent reduction in EGFR phosphorylation at a concentration of 1.20 µM with slight activity on the phosphorylation of MEK1/2 and ERK1/2. It also inhibits MRP2 expression in a dose-dependent manner with 24% inhibition and arrested the cells in the S phase of the cell cycle. Interestingly, compound 14a (estratetraene core) exhibited a twofold increase in anti-proliferative activity against both HepG2 and HepG2-R in comparison with the lead estratriene analog, demonstrating the significance of the designed ∆-16 unsaturation. The results shed a light on compound 14a and support further investigations to combat multidrug resistance in chemotherapy of hepatocellular carcinoma patients.

The aim of this review is to explore how diet and dietary supplements influence the activity of key multidrug resistance (MDR) transporters-MRP2, BCRP, and P-gp. These transporters play a crucial role in drug efflux from cancer cells and significantly affect chemotherapy outcomes. This review focuses on how dietary phytochemicals, such as catechins and quercetin, impact the expression and function of these transporters. Both in vitro and in vivo experiments were examined to assess changes in drug bioavailability and intracellular drug accumulation. The findings show that certain dietary components-such as catechins, flavonoids, resveratrol, curcumin, terpenoids, sterols, and alkaloids-can either inhibit or induce MDR transporter activity, thus influencing the effectiveness of chemotherapy. These results highlight the importance of understanding diet-drug interactions in cancer therapy to improve treatment outcomes and reduce side effects. In conclusion, dietary modifications and supplements should be carefully considered in cancer treatment plans to optimize therapeutic efficacy.

Cyclosporine-A (CsA) is currently used to treat immune rejection after organ transplantation as a commonly used immunosuppressant. Liver injury is one of the most common adverse effects of CsA, whose precise mechanism has not been fully elucidated. Pregnane X receptor (PXR) plays a critical role in mediating drug-induced liver injury as a key regulator of drug and xenobiotic clearance. As a nuclear receptor, PXR transcriptionally upregulates the expression of drug-metabolizing enzymes and drug transporters, including cytochrome P4503A (CPY3A) and multidrug resistance-associated protein 2 (MRP2). Our study established CsA-induced cytotoxic hepatocytes in an in vitro model, demonstrating that CsA dose-dependently increased the aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) level secreted in the HepG2 cell supernatant, as well as viability and oxidative stress of HepG2 cells. CsA also dose-dependently decreased the PXR, CYP3A4, CPY3A5, and MRP2 levels of HepG2 cells. Mechanistically, altering the expression of PXR, CYP3A4, CYP3A5, and MRP2 affected the impact of CsA on AST and LDH levels. Moreover, altering the expression of PXR also changed the level of CYP3A4, CPY3A5, and MRP2 of HepG2 cells treated by CsA. Our presented findings provide experimental evidence that CsA-induced liver injury is PXR tightly related. We suggest that PXR represents an attractive target for therapy of liver injury due to its central role in the regulation of the metabolizing enzymes CYP3A and MRP2-mediated bile acid transport and detoxification.

BACKGROUND: Chronic inflammation is considered to be a risk factor for carcinogenesis, tumor development and metastasis by providing tumor-related factors. OBJECTIVES: We aimed to evaluate the effect of cytokine interleukin-1β (IL-1β) as a key mediator of inflammation on multidrug resistance associated protein 2 (MRP2) expression and tamoxifen toxicity in estrogen receptor positive (ER+) MCF-7 breast cancer cells. METHODS: The effects of IL-1β on tamoxifen toxicity following 20-day treatment of MCF-7 cells with IL-1β and/or 17β-estradiol (E2) were measured by MTT assay. Furthermore, the effects of IL-1β and/or E2 on the mRNA expression and protein levels of MRP2 and NF-κB (p65) in breast cancer cells were evaluated by QRT-PCR and Western blot analysis, respectively. RESULTS: Treatment of breast cancer cells with IL-1β+ E2 decreased the sensitivity to 4-OH tamoxifen compared to both E2-treated and untreated cells. The mRNA expression levels of MRP2 and NF-κB (p65) were significantly increased following treatment with IL-1β+ E2, compared to control. In addition, breast cancer cells treatment with IL-1β+ E2 increased protein expression of MRP2 and it had no significant effect on NF-κB/p65 protein expression in these cells. CONCLUSION: Increased expression of mRNA and protein level of MRP2 following 20-day treatment of MCF-7 cells with IL-1β + E2 might be a possible elucidation for the increased tamoxifen resistance which was observed in these cells. More researches are essential to clarify the molecular mechanisms of inflammation on drug-resistance in the tumor environment in order to reducing or eliminating chemotherapy resistance and developing more effective treatment strategies. [ABSTRACT FROM AUTHOR]

• Changes in MRP2 expression play an important role in the development of chronic pulmonary inflammation. • CSE combined with LPS induced the downregulation of MRP2 expression in a time-dependent manner. • FXR can regulate the expression of MRP2 in the lung. • Overexpression of FXR can reduce chronic pulmonary inflammation by upregulating MRP2 expression. The transporter multidrug resistance protein 2 (MRP2) plays an important role in chronic pulmonary inflammation by transporting cigarette smoke and other related inflammatory mediators. However, it is not completely clear whether pulmonary inflammation caused by cigarette smoke extract (CSE) and lipopolysaccharide (LPS) is related to MRP2 and its signal factors. In this study, CSE combined with LPS was used to establish an inflammation model in vivo and in vitro. We found that compared with the control group, after CSE combined with LPS treatment, the expression of MRP2 in rat lung tissue in vivo and human alveolar cell line in vitro was down-regulated, while the expression of inflammatory factors was up-regulated. Through silencing and overexpression of FXR, it was found that silent FXR could down-regulate MRP2 and up-regulate the expression of inflammatory factors. On the contrary, overexpression of FXR could up-regulate MRP2 and down-regulate the expression of inflammatory factors. Our results show that CSE combined with LPS can down-regulate the expression of MRP2 under inflammatory conditions, and the down-regulation of MRP2 expression may be achieved partly through the FXR signal pathway. [ABSTRACT FROM AUTHOR]

Mercury is a widespread pollutant. Mercuric ions uptake into tubular cells is supported by the Organic anion transporter 1 (Oat1) and 3 (Oat3) and its elimination into urine is through the Multidrug resistance-associated protein 2 (Mrp2). We investigated the effect of recombinant human erythropoietin (Epo) on renal function and on renal expression of Oat1, Oat3, and Mrp2 in a model of mercuric chloride (HgCl2)-induced renal damage. Four experimental groups of adult male Wistar rats were used: Control, Epo, HgCl2, and Epo + HgCl2. Epo (3000 IU/kg, b.w., i.p.) was administered 24 h before HgCl2 (4 mg/kg, b.w., i.p.). Experiments were performed 18 h after the HgCl2 dose. Parameters of renal function and structure were evaluated. The protein expression of Oat1, Oat3 and Mrp2 in renal tissue was assessed by immunoblotting techniques. Mercury levels were determined by cold vapor atomic absorption spectrometry. Pretreatment with Epo ameliorated the HgCl2-induced tubular injury as assessed by histopathology and urinary biomarkers. Immunoblotting showed that pretreatment with Epo regulated the renal expression of mercury transporters in a way to decrease mercury content in the kidney. Epo pretreatment ameliorates HgCl2-induced renal tubular injury by modulation of mercury transporters expression in the kidneys. [ABSTRACT FROM AUTHOR]

Dubin-Johnson syndrome (DJS) is a rare autosomal recessive disorder that typically manifests in young adulthood as jaundice with conjugated hyperbilirubinemia. We report a case presenting as neonatal cholestasis with the unexpected histologic finding of paucity of interlobular bile ducts, a feature that is not typically seen in DJS. The diagnosis was confirmed by absent canalicular multidrug-resistance-associated protein 2 (MRP2) immunohistochemical staining on liver biopsy tissue and molecular genetic testing that demonstrated heterozygous mutations in the ATP-Binding Cassette Subfamily C Member 2 (ABCC2) gene, including a novel missense mutation. This report describes a case of DJS with atypical clinicopathologic findings and suggests that DJS should be considered in patients with neonatal cholestasis and bile duct paucity. [ABSTRACT FROM AUTHOR]

Background: Hyperbilirubinemia is a predictor of severe drug-induced liver injury (DILI). Hepatobiliary ATP-binding cassette (ABC) transporters play an important role in the transportation of many drugs and bilirubin; however, little is known about these transporters and the risk of DILI. The aim of this study was to explore associations between genetic variations in important ABC transporters and susceptibility to DILI, with a particular focus on hyperbilirubinemia. Methods: A total of 200 patients with DILI and 200 healthy controls were enrolled as the training dataset. Another 106 patients with DILI were recruited as the validation dataset. They were genotyped for ABCB11 (BSEP) rs2287622, ABCB1 (MDR1) rs1128503, rs1045642, ABCB4 (MDR3) rs2230028, ABCC2 (MRP2) rs1885301, rs717620, rs2273697, rs3740066 and rs8187710 using polymerase chain reaction-based TaqMan genotyping assays. Results: There were no statistical differences in any of the nine ABC transporter single nucleotide polymorphisms between the DILI and control groups. However, in the DILI group, the patients with hyperbilirubinemia had a higher frequency of the ABCC2 rs717620 C/T and T/T genotypes than those without hyperbilirubinemia (44.2% vs 20.2%, p = 0.001). After adjusting for other confounding factors, the ABCC2 rs717620 T variant was still associated with an increased risk of hyperbilirubinemia (adjusted odds ratio [OR]: 3.83, 95% confidence interval [CI]: 1.73-8.48, p = 0.001). This association was confirmed by the validation dataset (adjusted OR: 3.92, 95% CI: 1.42-10.81, p = 0.015). We also found that the mortality group had higher frequencies of the ABCC2 (MRP2) rs717620 C/T and T/T genotypes than the survival group (50.0% vs 27.9%, p = 0.048). Conclusion: Carriage of the ABCC2 (MRP2) rs717620 T variant may increase the risk of hyperbilirubinemia and mortality in patients with DILI. Screening for this variant may help to prevent and mitigate drug-induced hyperbilirubinemia. [ABSTRACT FROM AUTHOR]

Objectives: ATP binding cassette (ABC) transporters are a major superfamily of drug transporters and provide active transport of diverse substrates across cell membranes of several cell types. Genetic variations that affect function in ABCC2 gene may alter therapeutic outcome and the risk of toxicity to substrate drugs. The goal of the current survey was to ascertain the allele and genotype frequencies of ABCC2 1249G>A polymorphism in a Turkish population and to compare the findings obtained with the frequencies of previously reported populations. Methods: The frequencies of the ABCC2 1249G>A gene polymorphism were determined in 101 healthy Turkish individuals using polymerase chain reaction-restriction fragment length polymorphism methods. Results: The frequencies of GG, GA and AA genotypes were 67.3%, 28.7% and 4.0%, respectively. The frequencies were 81.7% for G allele and 18.3% for A allele. The frequencies of genotypes were in concurrence with Hardy-Weinberg Equilibrium. Significant distinctions were observed in the comparison of the study data with the results of some populations of East and South Asian ancestries. Conclusions: The current study presents the distribution of genotype and allele frequencies of ABCC2 1249G>A polymorphism in the Turkish population. As far as is known, this is the first study about the frequencies of the ABCC2 1249G>A polymorphism in the Turkish population. This study may ensure valuable information for evaluating inter-individual differences in drug response, estimating adverse reactions and improving disease management, briefly, it can contribute to pharmacogenetic and epidemiological studies. [ABSTRACT FROM AUTHOR]

Aim: MRP2 is an intestinal ABC transporter that prevents the absorption of dietary xenobiotics. The aims of this work were: (1) to evaluate whether a short‐term regulation of intestinal MRP2 barrier function takes place in vivo after luminal incorporation of nutrients and (2) to explore the underlying mechanism. Methods: MRP2 activity and localization were assessed in an in vivo rat model with preserved irrigation and innervation. Nutrients were administered into distal jejunum. After 30‐minutes treatments, MRP2 activity was assessed in proximal jejunum by quantifying the transport of the model substrate 2,4‐dinitrophenyl‐S‐glutathione. MRP2 localization was determined by quantitative confocal microscopy. Participation of extracellular mediators was evaluated using selective inhibitors and by immunoneutralization. Intracellular pathways were explored in differentiated Caco‐2 cells. Results: Oleic acid, administered intraluminally at dietary levels, acutely stimulated MRP2 insertion into brush border membrane. This was associated with increased efflux activity and, consequently, enhanced barrier function. Immunoneutralization of the gut hormone glucagon‐like peptide‐2 (GLP‐2) prevented oleic acid effect on MRP2, demonstrating the participation of this trophic factor as a main mediator. Further experiments using selective inhibitors demonstrated that extracellular adenosine synthesis and its subsequent binding to enterocytic A2B adenosine receptor (A2BAR) take place downstream GLP‐2. Finally, studies in intestinal Caco‐2 cells revealed the participation of A2BAR/cAMP/PKA intracellular pathway, ultimately leading to increased MRP2 localization in apical domains. Conclusion: These findings reveal an on‐demand, acute regulation of MRP2‐associated barrier function, constituting a novel physiological mechanism of protection against the absorption of dietary xenobiotics in response to food intake. [ABSTRACT FROM AUTHOR]

Background: 2,3,5,4′-tetrahydroxystilbence-2-O-β-D-glucoside (TSG) is a polyhydroxyphenolic compound, which exhibited a broad spectrum of pharmacological activities, such as anti-inflammatory, anti-depression, anti-oxidation and anti-atherosclerosis. However, the compound had poor bioavailability and the underlying absorption mechanisms had not been studied. Therefore, the purpose of this study was to investigate the intestinal absorption mechanism of TSG. Methods: This study used Caco-2 cell monolayer model and single-pass intestinal perfusion model to explore the gastrointestinal absorption mechanisms of TSG. The effects of basic parameters such as drug concentration, time and pH on the intestinal absorption of TSG were analyzed by high performance liquid chromatography. The absorption susceptibility of TSG to three inhibitors, P-gp inhibitors verapamil hydrochloride and quinidine, and MRP2 inhibitor probenecid were also assessed. Results: TSG was poorly absorbed in the intestines and the absorption of TSG in stomach is much higher than that in intestine. Both in vitro and in situ experiments showed that the absorption of TSG was saturated with increasing concentration and it was better absorbed in a weakly acidic environment pH 6.4. Moreover, TSG interacts with P-gp and MRP2, and TSG was not only the substrate of the P-gp and MRP2, but also affected the expression of P-gp and MRP2. Conclusions: It was concluded that the gastrointestinal absorption the most unique active ingredient and considered as the mechanisms of TSG involved processes passive transport and the participation of efflux transporters. [ABSTRACT FROM AUTHOR]

Purpose: Our aim was to evaluate the influence of genetic polymorphisms involved in the metabolism and transportation of deferasirox on deferasirox pharmacokinetics in the Chinese population. Methods: Thirty-eight healthy Chinese subjects were administered with a single dose of 20 mg kg−1 deferasirox. Allelic discriminations for eight single-nucleotide polymorphisms (SNPs) in UDP-glucuronosyltransferase 1A1, 1A3 (UGT1A1, UGT1A3), multidrug resistance protein 2 (MRP2, ABCC2), and breast cancer resistance protein (BCRP, ABCG2) were performed. The concentrations of deferasirox in the plasma were determined by UPLC-MS/MS. Results: Subjects carrying ABCC2 c.-24 T allele had a 65% higher clearance (CL/F) and 42% lower area under the concentration–time curve from 0 to 72 h (AUC0-72h) as compared with non-carriers (P = 0.008, P = 0.011, respectively). ABCC2 c.-24 T was also associated with 59% shorter half-life (T1/2) and 17% shorter mean residence time (MRT) (P = 0.030, P = 0.014, respectively). ABCC2 1249A was associated with a marginal increase in deferasirox Cmax (P = 0.07). Genetic polymorphisms of UGT1A1, UGT1A3, and ABCG2 did not significantly influence the pharmacokinetics of deferasirox. Subjects with UGT1A1 211GG-(-1352)CC-(-3156)GG haplotype had higher AUC0-72h than others. Since only two subjects were recruited in the GG-CC-GG group, further confirmative studies were warranted. Conclusions: ABCC2 c.-24 C>T was associated with the pharmacokinetic variability of deferasirox in Chinese subjects. This study revealed an important role of MRP2 in the pharmacokinetics of deferasirox and drew attention to drug combination with MRP2 inhibitors like cyclosporine and methotrexate in deferasirox therapy. [ABSTRACT FROM AUTHOR]

This article describes the realisation of an optimisation project by a global chemical manufacturer with the objective of developing and implementing a supply chain coordination tool. After a presentation of the current supply chain and the challenges faced by Solutia prior to the optimisation project, we provide an overview of the mathematical model depicting the company's worldwide production network. We then provide an insight into the lessons learned by both the optimisation team and supply chain managers. In addition to the financial benefits, the project contributed to the structuring of scattered knowledge throughout a complex supply chain. We also address the shortcomings of ERP systems when it comes to providing reliable planning data and, in this context, draw parallels between optimisation and software development projects. [ABSTRACT FROM AUTHOR]

Background: Cholestasis is a common pathological manifestation dominated by accumulation of potentially toxic biliary compounds. Na + -taurocholate cotransporting polypeptide (NTCP) plays a critical role in protection from cholestasis and can be targeted therapeutically. Chishao ( Paeoniae Radix Rubra ) is a clinically efficacious agent for treating cholestasis, but the underlying mechanism has not been fully clarified. Objective: To evaluate the effects of Chishao on the expression of NTCP in rats with alpha-naphthylisothiocyanate (ANIT)-induced cholestasis. Methods: Chishao extracts were obtained by water decoction. Cholestasis model induced by ANIT in rats were established. Thirty rats were divided into five groups: control group (C), ANIT model group (M), 10 g/kg Chishao group (LD), 20 g/kg Chishao group (MD) and 40 g/kg Chishao group (HD). The levels of serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TB), direct bilirubin (DB), alkaline phosphatase (ALP) and total bile acid (TBA) were detected. The mRNA and protein expression of NTCP, multidrug resistance associated protein 2 (MRP2) and bile salt export pump (BSEP) were detected by reverse transcription qPCR and Western blotting respectively. To assess the effects of Chishao on NTCP, MRP2 and BSEP localized at the membrane of hepatocytes, an in vitro experiment involving primary hepatocytes was conducted via the utilization of laser scanning confocal microscopy. Results: The extracts of Chishao significantly improved serum ALT, AST, ALP, TB, DB and TBA ( p < 0.05), especially ALP in the HD group ( p < 0.01). The histological pathological findings were also reversed in LD, MD and HD groups. The mRNA level of MRP2 was significantly downregulated after treatment with ANIT, whereas it was reversed in MD and HD groups ( p < 0.05). The mRNA expression of NTCP was significantly downregulated after ANIT treatment, but dramatically upregulated in the HD group. The expressions of BSEP and MRP2 were similar, but that of NTCP decreased after ANIT treatment, which was reversed significantly by Chishao extracts in a dose-dependent manner. The expression of NTCP in hepatocytes from rats increased dose-dependently after Chishao treatment in vitro . Conclusion: Chishao extracts can improve the serum and histological performances of intra-hepatic cholestasis caused by ANIT, probably by working on transport proteins in liver cell membranes., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Sun, Fang and Fang.)

Despite being one of the most frequently used chemotherapy agents, cisplatin exhibits substantial hepatorenal injury by triggering oxidative stress, inflammation, and apoptosis pathways. The current investigation studied the possible protective effects of calcitriol on cisplatin-induced hepatorenal toxicity. Mice were divided randomly as follows: control group, calcitriol group (received calcitriol 5 µg/kg, p.o. for 14 days), cisplatin group (received a single i.p. injection of cisplatin 10 mg/kg on the 10th day), and calcitriol + cisplatin group (received calcitriol 5 µg/kg, p.o. for 14 days and cisplatin 10 mg/kg, i.p. on the 10th day). The possible interaction between calcitriol and cisplatin on cell viability was tested in HepG2 cells by MTT assay. Hepatorenal toxicity induced by cisplatin was reversed by calcitriol, as evidenced by improved histological examinations and liver and kidney function tests. In addition, calcitriol counteracted oxidative stress and enhanced Nrf2 and Mrp2 expression in the liver and kidney while suppressing levels of p38 MAPK in cisplatin-treated mice. Calcitriol also inhibited cisplatin-induced hepatic and renal inflammation, as determined by suppressing TNF-α and enhancing IL-10 levels. By downregulating caspase-3, calcitriol also promoted liver and kidney tissue survival in mice treated with cisplatin. Moreover, cisplatin's cytotoxic effects were significantly potentiated when calcitriol was combined with cisplatin. The current study showed that calcitriol protects against cisplatin-induced hepatorenal injury by suppressing oxidative stress, inflammation, and apoptosis, which the Nrf2-Mrp2/p38 MAPK pathway might regulate., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Many widespread and persistent organic pollutants, for example, 2,3,7,8-tetrachlorodibenzo-pdioxin (TCDD) and some polychlorinated biphenyls, activate the aryl hydrocarbon receptor (AhR) causing it to translocate to the cell nucleus where it transactivates target genes, increasing expression of a number of xenobiotic metabolizing enzymes as well as some transporters. AhR’s ability to target transporters within the kidney is essentially unexplored. We show here that exposing isolated killifish (Fundulus heteroclitus) renal proximal tubules to micromolar β-naphthoflavone (BNF) or nanomolar TCDD roughly doubled the transport activity of Multidrug resistance-associated proteins Mrp2 and Mrp4, P-glycoprotein (P-gp) and Breast cancer resistance protein (Bcrp), all ATP-driven xenobiotic efflux pumps and critical determinants of renal xenobiotic excretion. These effects were abolished by actinomycin D and cycloheximide and by the AhR antagonist, α-naphthoflavone, indicating that increased transport activity was dependent on transcription and translation as well as ligand binding to AhR. Quantitative immunostaining of renal tubules exposed to BNF and TCDD showed increased luminal membrane expression of Mrp2, Mrp4, P-gp and Bcrp. Thus, in these renal tubules, the four ABC transporters are targets of AhR action. [ABSTRACT FROM AUTHOR]

Highlights • MRP2 was stably expressed in MDCK/MRP2 cells. • 8 of 35 flavonoids were identified as substrates of MRP2 in MDCK/MRP2 cells. • SAR and docking were done for structure requirements of flavonoid substrates. • 3,5,6,3′-OH, 4′-OCH 3 favoured but 8,3′-OCH 3 , 2′,4′,5′-OH disfavoured for MRP2 affinity. Abstract This study was aimed to determine the relationship of flavonoid structures to their affinity for an important efflux transporter, multidrug-resistant associated protein 2 (MRP2). The cellular uptake (CU) of 35 flavonoids was investigated in MRP2 overexpression MDCK/MRP2 cells. Resulting data identified 8 flavonoids as MRP2 substrates based on their high CU MK with MK-571 in MDCK/MRP2 cells. Also, three substrates showed better CU MD in MDCK cells than did CU MRP in MDCK/MRP2 cells. Docking analyses showed a good correlation (R = 0.926, p = 0.003) between efflux-fold of flavonoid substrates and their docking S_scoring with the MRP2 model, indicating consistency between in silico and in vitro approaches. A structure affinity relationship (SAR) study indicated that 3-OH, 5-OH, 6-OH, 3′-OH, and 4′-OCH 3 substituents were favourable while, 8-OCH 3 , 2′-OH, 3′-OCH 3 , 4′-OH and 5′-OH were unfavourable for flavonoid affinity to MRP2. Our study provides valuable information for dietary application of flavonoids with specific structures for high absorption. [ABSTRACT FROM AUTHOR]

Taurolithocholate (TLC) is a cholestatic bile salt that induces disinsertion of the canalicular transporter Abcc2 (Mrp2, multidrug resistance-associated protein 2). This internalization is mediated by different intracellular signaling proteins such as PI3K, PKCε and MARCK but the initial receptor of TLC remains unknown. A few G protein-coupled receptors interact with bile salts in hepatocytes. Among them, sphingosine-1 phosphate receptor 2 (S1PR2) represents a potential initial receptor for TLC. The aim of this study was to evaluate the role of this receptor and its downstream effectors in the impairment of Abcc2 function induced by TLC. In vitro, S1PR2 inhibition by JTE-013 or its knockdown by small interfering RNA partially prevented the decrease in Abcc2 activity induced by TLC. Moreover, adenylyl cyclase (AC)/PKA and PI3K/Akt inhibition partially prevented TLC effect on canalicular transporter function. TLC produced PKA and Akt activation, which were blocked by JTE-013 and AC inhibitors, connecting S1PR2/AC/PKA and PI3K/Akt in a same pathway. In isolated perfused rat liver, injection of TLC triggered endocytosis of Abcc2 that was accompanied by a sustained decrease in the bile flow and the biliary excretion of the Abcc2 substrate dinitrophenyl-glutathione until the end of the perfusion period. S1PR2 or AC inhibition did not prevent the initial decay, but they accelerated the recovery of these parameters and the reinsertion of Abcc2 into the canalicular membrane. In conclusion, S1PR2 and the subsequent activation of AC, PKA, PI3K and Akt is partially responsible for the cholestatic effects of TLC through sustained internalization of Abcc2. [ABSTRACT FROM AUTHOR]

Capsaicin (trans‐8‐methyl‐N‐vanillyl‐6‐nonenamide, CAP) is an important ingredient in spicy foods consumed throughout the world. Vinblastine (VBL) is a naturally occurring alkaloid prescribed to cancer patients. Many cancer patients treated with VBL were taking CAP at the same time. This study attempted to investigate the effect of CAP on the pharmacokinetics of VBL, which is the substrate of CYP3A, P‐gp, and Mrp2. CAP, cyclosporine (CsA) or olive oil was given to rats for seven consecutive days, and on the seventh day, VBL (1.3 mg/kg) was administered intravenously. CsA was used as a CYP3A1/2 and transporter inhibitor, and olive oil was used as a vehicle. The results showed that pretreatment of rats with CAP (3.0 mg/kg) for seven consecutive days resulted in an increase in the AUC0–t of VBL of about 29.8% (P < 0.05) compared with the control group. Moreover, CAP decreased the CL of VBL to 75.5% (P < 0.05). At this time, CYP3A1/2 and Mrp2/Abcc2 in the liver was decreased at the mRNA and protein levels. These results demonstrate that chronic ingestion of CAP will increase systemic exposure and reduce clearance of VBL in rats. The food–drug interaction between CAP and VBL appears to be due to modulation of CYP3A1/2 and Mpr2 expression by CAP. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the ability of non-ionic surfactants to inhibit MRP2-mediated transport in vitro in MDCKII MRP2 cells. Transport studies across MDCKII MRP2 cell monolayers were performed using 3H-etoposide and 3H-digoxin. 19 different non-ionic surfactants, including several polysorbates (PS), cremophor EL, vitamin E-TPGS, and n -nonyl β-D-glucopyranoside (NG), were investigated. Barrier function of the cells was investigated measuring TEER and transport of 14C-glycine. The amount of isotope was quantified using liquid scintillation counting. In MDCKII MRP2 cells a polarized transport of etoposide and digoxin in the secretory (basolateral to apical) direction with efflux ratios of 5.5 ± 0.7 and 18.5 ± 4.2, respectively, was measured. P-gp inhibitors such as valspodar and zosuquidar did not affect etoposide transport, and furthermore PS20 decreased secretory transport of digoxin, but not of etoposide. Transport of etoposide was therefore mainly MRP2-mediated and used as a probe to investigate pharmaceutical excipients. Non-ionic surfactants did not modulate etoposide transport across intact cell monolayers of MRP2 overexpressing MDCKII cells, although preliminary studies suggest that most were able to alter MRP2-mediated efflux of the fluorescent 5-chloromethylfluorescein (CMF). In conclusion, etoposide transport across MDCKII MRP2 cells was modulated by cyclosporin A, an inhibitor of MRP2 and P-gp, but not by specific P-gp inhibitors (valspodar and zosuquidar), which suggests that etoposide transport is primarily influenced by MRP2. In addition, commonly used non-ionic surfactants did not decrease MRP2-mediated etoposide transport in MDCKII MRP2 cells. These results suggest that etoposide transport in MDCKII MRP2 cells is a model system to investigate MRP2 interactions, and that surfactants may not have a large potential for increasing oral bioavailability of drugs through inhibition of MRP2 transport activity. [ABSTRACT FROM AUTHOR]

TNFα is a cytokine whose levels are increased in inflammatory pathologies that are associated with cholestasis. Endocytic internalization of Abcc2 (multidrug resistance-associated protein 2), a canalicular transporter of organic anions that is implicated in the clearance of clinically important drugs, is a phenomenon that occurs in inflammatory liver diseases, and it has been established that cytokines act as mediators. However, the intracellular mechanism involved in this effect remains unknown. The aim of the present work was to characterize the internalization of Abcc2 induced by TNFα and to study the role of ERK1/2 and reactive oxygen species as signaling mediators of transporter internalization. Using rat hepatocyte couplets, we found that TNFα (6.25 pg/ml) induced a decrease in Abcc2 activity estimated by the accumulation of the Abcc2 substrate glutathione methylfluorescein in the canalicular vacuole that was accompanied by internalization of Abcc2 from the canalicular membrane. Inhibition of MEK1/2 (upstream of ERK1/2) partially prevented TNFα effects on Abcc2 internalization and activity impairment. Reactive oxygen species (ROS) scavengers such as vitamin C and mannitol partially prevented both TNFα-induced decrease in Abcc2 activity and ERK1/2 phosphorylation. Apocynin, a NADPH oxidase inhibitor, prevented the increase in ROS and the phosphorylation of ERK1/2 produced by TNFα. Taken together, these results indicate that TNFα activates a pathway involving NADPH oxidase, ROS and MEK1/2-ERK1/2 that is partially responsible for the internalization of Abcc2. This internalization leads to an altered transport activity of Abcc2 that could impair drug disposal, enhancing drug toxicity in patients suffering from inflammatory liver diseases. [ABSTRACT FROM AUTHOR]

Intestinal multidrug resistance-associated protein 2 is an ABC transporter that limits the absorption of xenobiotics ingested orally, thus acting as essential component of the intestinal biochemical barrier. Metabolic Syndrome (MetS) is a pathological condition characterized by dyslipidemia, hyperinsulinemia, insulin resistance, chronic inflammation, and oxidative stress (OS). In a previous study we demonstrated that MetS-like conditions induced by fructose in drinking water (10% v/v, during 21 days), significantly reduced the expression and activity of intestinal Mrp2 in rats. We here evaluated the potential beneficial effect of geraniol or vitamin C supplementation, natural compounds with anti-inflammatory and anti-oxidant properties, in reverse fructose-induced Mrp2 alterations. After MetS-like conditions were induced (21 days), animals were cotreated with geraniol or vitamin C or vehicle for another 14 days. Decreased expression of Mrp2 protein and mRNA due to fructose administration was reversed by geraniol and by vitamin C, consistent with restoration of Mrp2 activity evaluated in everted intestinal sacs. Concomitantly, increased intestinal IL-1β and IL-6 levels induced by fructose were totally and partially counterbalanced, respectively, by geraniol administration. The intestinal redox unbalance generated by fructose was improved by geraniol and vitamin C, as evidenced by decreasing lipid peroxidation products and activity of Superoxide Dismutase and by normalizing glutathione reduced/oxidized glutathione ratio. The restoration effects exhibited by geraniol and vitamin C suggest that local inflammatory response and OS generated under MetS-like conditions represent important mediators of the intestinal Mrp2 down-regulation. Additionally, both agents could be considered of potential therapeutic value to preserve Mrp2 function under MetS conditions. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Design and synthesis of a novel series of nitric oxide donating Cucurbitacin Inspired Estrone Analogs (NO-CIEAs). • Binding affinity of NO-CIEA 17 and 20a towards EGFR and ERK was suggested by docking study. • Anti-proliferative activity was examined against HepG2 and Erlotinib-resistant HepG2 cell lines. • Intracellular NO release was examined using NO-sensitive fluorophore DAF-FM DA. • Flow cytometric studies showed that both 17 and 20a mainly arrested the HepG2 cells in the G0/G1 phase. • ICW assay revealed the dual inhibitory activity of NO-CIEA 17 towards EGFR and ERK in a dose dependent manner. • The significant impact on the chemotherapeutic resistance was confirmed by inhibition of MRP2 in a dose dependent manner by NO-CIEA 17. Abstract Development of hybrid drug candidates is well known strategy for designing antitumor agents. Herein, a novel class of nitric oxide donating cucurbitacin inspired estrone analogs (NO-CIEAs) were designed and synthesized as multitarget agents. Synthesized analogs were initially evaluated for their anti -hepatocellular carcinoma activities. Among the tested analogs, NO-CIEAs 17 and 20a exhibited more potent activity against HepG2 cells (IC 50 = 4.69 and 12.5 µM, respectively) than the reference drug Erlotinib (IC 50 = 25 µM). Interestingly, NO-CIEA 17 exerted also a high potent activity against Erlotinib-resistant HepG2 cell line (HepG2-R) (IC 50 = 8.21 µM) giving insight about its importance in drug resistance therapy. Intracellular measurements of NO revealed that NO-CIEAs 17 and 20a showed a significant increase in NO production in tumor cells after 1 h of incubation comparable to the reference prodrug JS-K. Flow cytometric analysis showed that both NO-CIEAs 17 and 20a mainly arrested the HepG2 cells in the G0/G1 phase. Also, In-Cell Based ELISA screening showed that NO-CIEA 17 resulted in a potential inhibitory activity towards the EGFR and MAPK (25% and 29% inhibition compared to untreated control cells, respectively). This data suggests the binding ability of NO-CIEA 17 to the EGFR and ERK to be well correlated along with the docking and cellular studies. Also, treatment of HepG2-R cells with NO-CIEA 17 showed a potential reduction of MRP2 expression in a dose dependent manner providing a significant impact on the chemotherapeutic resistance. Overall, the current study provides a potential new approach for the discovery of a novel antitumor agent against HCC. [ABSTRACT FROM AUTHOR]

Abstract Background The effect of hepatic ischemia–reperfusion injury (IRI) on bile transporter (BT) gene expression is unknown. We hypothesized that abnormal expression of BTs during hepatic IRI is dependent on nuclear factor erythroid 2–related factor 2 (NRF2), which contributes to the cholestasis after reperfusion. Methods Sham surgery and short (60 min) or long (90 min) periods of warm ischemia time (WIT) with or without reperfusion for 24 h were applied to wild-type Sprague–Dawley rats and Nrf2 knockout rats (n = 5 per group). At each stage of IRI, the serum levels of aminotransferase, total bilirubin, and bile acids were measured. In addition, hepatic tissue was sampled to determine the histologic score of IRI (Suzuki score), measure adenosine triphosphate (ATP), and identify the quantitative real-time polymerase chain reactions of BTs (Oatp1 , Ntcp , Mrp2 , Bsep , and Mrp3). Results In short periods of WIT, BT expression increased during the ischemia stage and returned to the baseline after reperfusion. However, in long periods of WIT, BT expression did not increase after ischemia and decreased further after reperfusion. Short WIT did not increase BT expression in Nrf2 knockout animals. The level of BT expression was correlated with the Suzuki score, the serum levels of aminotransferase, bilirubin, and bile acids, and tissue ATP level. Stepwise multiple regression analysis derived equations to predict the Suzuki score (R 2 = 76.8, P < 0.001), serum total bilirubin (R 2 = 61.2, P < 0.001), and tissue ATP (R 2 = 61.1, P < 0.001). Conclusions Short WIT induces the transcriptional activities of BT, whereas long WIT depresses them, and the effect was blunted by Nrf2 knockout status. BT expression can be considered a surrogate marker for hepatic IRI. [ABSTRACT FROM AUTHOR]

Background: Although silybin serves as a well-known hepatoprotective agent with prominent anti-inflammatory, anti-oxidant and anti-fibrotic activities, its low bioavailability limits its application in the treatment of chronic liver diseases. However, novel formulation products with increased solubility were not sufficient to achieve pharmacologically meaningful concentrations of silybin in the clinical studies even used at high dosage.Hypothesis/purpose: We hypothesized that inhibiting efflux transporter(s) and/or glucuronidation by piperine might enhance the bioavailability and efficacy of silybin.Methods: Pharmacokinetics of silybin given alone or in-combination with piperine was determined by a validated LC-MS method. A CCl4 induced rat model of liver injury was prepared and verified for comparing the effects of silybin and combination treatment. To investigate the underlying mechanism, the inhibition effects of piperine on transportation of silybin were performed in Caco-2 and transfected MDCKII cell lines as well as sandwich-cultured rat hepatocytes (SCH). Human liver microsomes incubation was used for exploring the modulation effects of piperine on the phase-2 metabolism of silybin.Results: In the present study, we demonstrated for the first time that piperine as a bioenhancer increased the bioavailability of silybin (146%- 181%), contributing to a boosted therapeutic effect in CCl4-induced acute liver-injury rat model. The underlying mechanisms involved that piperine enhanced the absorption of silybin by inhibiting the efflux transporters including MRP2 and BCRP but not MDR1 in Caco-2 and transfected MDCKII cell lines. Moreover, piperine could inhibit the biliary excretion of silybin and conjugated metabolites in sandwich-cultured rat hepatocytes. Notably, we found that piperine did not affect the phase-2 metabolism of silybin.Conclusion: Efflux transporters play an important role in the pharmacokinetic behavior of flavolignans, and modulating these transporters by bioenhancer such as piperine could enhance the in vivo absorption of silybin, leading to more effective treatments. [ABSTRACT FROM AUTHOR]

Résumé: L'évaluation et la prise en charge des maladies du foie sont essentielles pour améliorer la survie des patients d'hématologie, notamment après greffe de cellules hématopoïétiques allogéniques. Donner un avis de consultant hépato-gastroentérologue est, en général, compliqué lorsque le patient a un cancer en cours de traitement, et qu'il développe un ictère, une prise de poids, une ascite, de la fièvre, des douleurs de l'hypochondre droit, et des tests hépatiques anormaux. Les avancées dans le domaine de la biologie moléculaire diagnostique et de l'imagerie ont rendu les démarches diagnostiques plus simples, et la biopsie hépatique n'est maintenant indiquée que dans de rares situations. Les algorithmes diagnostiques et thérapeutiques sont plus clairs pour orienter le clinicien et débuter rapidement un traitement. L'hématologie est une spécialité en pleine expansion et de nombreux médicaments arrivent sur le marché sans que leur sécurité hépatique soit parfaitement cernée. L'objectif de cette revue est de fournir au lecteur les clés pour être un praticien averti dans le domaine des maladies du foie des patients d'hématologie. The evaluation and management of liver diseases is essential to improve the survival of hematology patients, especially after transplantation of allogeneic hematopoietic cells. The consulting hepatologist may never see a more complex patient than a patient with cancer who develops jaundice, fluid retention, fever, liver pain, and abnormal serum liver tests – and in contrast to the situation where patients have a single diagnosis, there may be multiple causes of liver dysfunction in such a patient. However, medical progress in liver imaging and molecular methods of viral diagnosis have made evaluations more straight-forward, such that liver biopsy can be confined to the most puzzling cases. Diagnostic and therapeutic algorithms are clearer in guiding the clinician and starting treatment quickly, but one long-term goal should be to prevent liver injury in the first place. Hematology is a growing specialty and many drugs are coming to the market without their liver safety being fully understood. The purpose of this review is to provide the reader with the keys to be a knowledgeable practitioner in the field of liver disease in hematology patients. [ABSTRACT FROM AUTHOR]